DCOM: CoCreateInstanceEx returns E_ACCESSDENIED - security

I'm working on a DCOM application with the server and client on two machines, both of which are running WinXP with Service Pack 2. On both machines, I'm logged in with the same username and password.
When the client on one machine calls CoCreateInstanceEx, asking the other machine to start up the server application, it returns E_ACCESSDENIED.
I tried going into the server app's component properties in dcomcnfg and giving full permisions to everyone for everything, but that didn't help.
What do I need to do to allow this call to succeed?
Update: When the server app is running on a Windows 2000 box, I do not get this error; CoCreateInstanceEx returns S_OK.

Right, so if your Authentication level is set to Default. What is the authentication level set to in the Default Settings? Just out of interest. (although the fact that it works to a 2000 box probably makes that redundant)
EDIT:
Also: I seem to remember doing a lot of rebooting when I used to play/work with DCOM so maybe a quick reboot of both machines when you're happy with the dcomcnfg settings wouldn't go amis either.

If the PCs aren't both members of the same domain, you need to also given launch & access permissions to "ANONYMOUS LOGON". "Everyone" does not include this.

Three things to check:
1) Go back to dcomcnfg and make try making sure that not just the access security but also the "launch permissions" section contains the appropriate security users or groups.
2) Ensure that the Authentication Level is set to something else other than "None"
3) Also check that the location on disk that the component is located is actually accessible to the account configured in the security permissions you set.
EDIT:
One more: Are you calling CoInitialiseSecurity() first too? That rings a bell!
EDIT2:
Based on your update: Try dropping the firewalls completely on both XP machines and see if that makes a difference. You may need to let DCOM through explicitly.

What is the flavor of your Windows 2000 box, btw? Professional, Server, Adv Server...
Also, is there a difference between domain membership between the two (one on a domain, the other not, different domains, etc...?)
One more thing - DCOM errors will appear in the System event log at times - especially for object creation - did you check there for clues?

I had the exact same problem.
The problem happens in machines that have XP SP2+ OS or newer.
I solved it using the following steps:
Verify that both client and server computers are on the same domain.
You need to use the same user in both computers, or, if you want to use different users in client and server you need to make sure that both client and server users have privliges on both computers (in particular - make sure that they are members of Distributed COM users group.
open Componenet services MMC (run dcomcnfg).
Go to My Computer->Properties->Default Properties and make sure that Default Impersenation Level is "Identify"
Go to COM Security tab, in both in Access permissions and Launch and activation permissions go to Edit Limits, and add Local and Remote access permissions to the client and server users of your COM application
Make sure that you have a firewall exception in port 135 for your application...
I hope this helps you!

Related

IIS 8.5 Windows Server 2012 ASP Classic/Active-X COM DLL issues writing to UNC shared folder

I have spent 12 hours on this, tried everything that I have read about, but I cannot get a new server farm we have,the website to write to a shared folder.
I have set the application pools, even temporarily (just to try it out) to admin accounts and even set the folder to be available for "everyone".
We have a network specialist who cannot figure it out either, in his favour he does not understand IIS very well and keeps away from it, but at the end of the day, its just a User account and permissions as far as I can see and I have set up the exact same website on a previous W2012 server and IIS 8.5, 7.5 and 6 without major issues (abeit registering 32bit DLLs in a 64bit environment) but all that has gone well and no issue (except for reading and writing to a shared folder).
SO breaking it down to its simplest form, I used a simple FSO script to write a text file in the shared folder, this clearly came back with "Permission denied line X".
Running the script through cscript as a VBS file, it works, running it through IIS. No chance.
Im not going to give up, but running as the top admin login (I had the network guy use HIS identity in the application pool) its not happening.
32bit has been enabled, yes, folder permissions set, yes.
Im at my wits end with the thing. Anything to suggest, I would be happy to listen and try.
Thanks all.
Update: I can write to the same MACHINE as IIS, any folder as long as I set the appropriate permissions. The difference between from this shared folder (I am working on a server farm, I forgot to mention that) is - when you do the security, locations "IIS AppPool\poolidentity" to add the user, it works on the same server, when I try to add that user on the shared folder on the networked server, that user does not appear - does this give any clues?
Ok - for me, after all the right things that I had done, was something I had not tried.
Select the site in IIS, so you sell all the icons for ASP, Authentication, Autohorization Rules, CGI etc.. - select the Authentication and Open Feature
You will see Anonymous Authentication (Enabled), ASP.NET Impersonation (Disabled), Basic Authentication (Disabled) and so on.
Select the Anonymous Authentication, right click Edit - by default it was set to "Specific User" IUSR - now for me, that did not work - so clicked on Application Pool Identity and boom, now its working.
Hope that helps someone else.

IIS Shared config - applicationHost.config Error: Cannot write configuration file due to insufficient permissions

I've setup a UNC share for IIS shared config using a specific AD service account and set to FULL CONTROL. I've also exported the config from one IIS server and set-up an additional IIS server to point to the share. When I open the applicationhost.config for example on the UNC share and remove an application pool, I can see the entry also remove in both IIS servers.
So I know:
1) I can export to the share with the specific service account
2) Both IIS servers can read the config when I edit manually
3) However when I remove an app pool from one of the IIS servers through the manager I get the above error.
I've tried using the process monitor utility to see what account is being used to write to the config and it seems it is my own AD user account rather than the shared service account. I know IIS Manager has my username e.g. ROOT\MYNAME logged on, but I wouldn't have thought it would use this to write changes to the shared config. Surely it would use the service account?
Does anyone know how to prevent this error? Why does the shared config and tied service account not come into play when making changes on one of the servers?
So, IMHO, this error is a red herring. I was publishing to a server and got a message saying I was out of space. So, I logged in, realized there was a bit of cruft in extra apps published in IIS, we didn't need. I right clicked and tried to remove one. I got the same error as you.
Having done some manual changes to applicationHost, I thought it "might be me" but it seemed very odd that editing this file would cause such a thing. However, I had recently learned that windows does some funky 32 vs 64bit machinations with this file (google it).
Deciding I had better things to do, I asked our IT to add space to the VM and guess what? I am no able to remove these apps. My guess is that I was at the end of the line on space and the backend management of these special files was not completing and throwing this not-so-helpful exception.
I'm not a 100% about this. For full disclosure, I will add that updates had been applied recently, but I'm pretty confident that this is a possible solution.

How to do remote staging in liferay 6.1.1 GA2?

I have a site when I tried to apply local staging it's worked fine,but we I tried to connect it through remote server it's not working giving error connection can't be established.Does any one tried it?
This is the configuration with the error message:
This blog post (disclaimer: my own) explains how to do it with https - you can omit long parts of it if you don't want encryption. It also covers 6.0, but the general principle is still the same.
You want to pay special attention to the paragraph Allow access to webservices in that article and check if your publishing server (the "stage") has access to the live server. In general, if this is not on localhost, it requires configuration as mentioned in that article.
As you indicate that you can't connect to your production server from your staging server, please check by opening a browser, running on the staging server and connect it to the production server - go to http://production-server-name:8080/api/axis and validate that you can connect (note: You get the authoritative result for this test only when not accessing localhost as the production system: Do run the browser on the staging system!) - with this test you can eliminate the first chance of your remote system being disallowed. Once this succeeds, you'll need credentials for the production server to be entered on the staging server - the account that you use needs to have permissions to change all the data it needs to change when publishing content (and pages etc.)
The error message you give in the added screenshot can appear when the current user on staging does not have access to the production system (with the credentials used) - verify that you have the same user account that you are using on your staging system (the one that gets the error message from the screenshot) in your production system. Synchronize the passwords of the two.
I your comment you give the information that you're using different version for the staging and the production environment - I don't expect that to work, so this might be the root cause. Test with both systems at the same version.
A couple important points to keep in mind with remote publishing:
If you're not on LDAP (or you have different LDAPs for different environments), you should validate that your user account is exactly the same in both source and target environments. So, if you're on the QA site and you want to remote publish to production, your screen name, email address, and password should all be the same.
Email address is uber important. Depending on which distribution (version) of Liferay you are on, the remote publish code uses your email address to irrespective of whether or not you have portal-ext.properties configured to use screenname.
You should have the Administrator role in on both sides. It may not be required in every scenario, but giving that role out to users that do remote publishing has saved me time and effort debugging why someone's remote publish didn't work. Debugging this process takes a very long time.
If remote publishing is causing you problems (and it probably is or you wouldn't be here), try doing lar file exports / imports. This is important since remote publish failures are not exactly helpful in telling you what failed, they just tell you then failed. Surprisingly, there are often problems in the export process and you can sometimes pinpoint some bad documents or a funky development thing you did using Global scope and portlet preferences that caused your RP to fail. I generally use this order in this situation a) documents and media [exclude thumbnails or your lar file will likely double in size, also exclude ranks if you're not using them] from the wrench icon in the control panel b) web content from the wrench icon in the control panel c) public pages [include data > web content display, but remove all the other data check boxes], include permissions, include categories d) private pages [same options as public pages].
If you already have Administrator role and it's saying you don't have permissions to RP to the remote site, setup your user on the target environment with the "Site Administrator" or "Site Owner" role.
A little late for first and foremost, but anytime you have something that's not working (remote publishing or otherwise), check the logs before you do anything else. The Liferay code base doesn't include a lot of helpful logging, but you do occasionally get a nugget of information that helps you piece together enough to do root cause analysis.
Cheers! HTH

How to view Windows Event Log remotely with limited privileges

To debug some code, I would like to view the Windows event log of a remote machine (target is Windows2003). With mmc.exe I can add the event log for a remote machine, but only if I have sufficient permissions. For this remote machine, they do not want to give me permissions to log in remotely (or admin privileges for that matter). Is there a specific permission I can be given to view the event log and not much else?
On newer Windows versions (Windows 7, Windows Server 2008...) you can simply add the corresponding account to the built-in group Event Log Readers.
Source: Jane Lewis's Weblog on TechNet, Giving Non Administrators permission to read Event Logs Windows 2003 and Windows 2008
This source also describes an alternative if you need more fine-grained control.
(The OP asked for Windows 2003, where this method doesn't work, but as Windows Server 2003 is no longer supported, people might be interested in this method.)
For the security log, users need the privilege "Manage auditing and security log"
For the system and applciation logs you should be able to read them as just a guest unless they have set the RestrictGuestAZccess value under the following registry keys:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\EventLog\System
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\EventLog\Application
One Option is to get a local ID that is on the remote local admin group.
Next, from your system, map to a drive on the remote server using the new remote local ID.
Create a new MMC from the Windows Run start menu - by typing in MMC /a
Add the EventView Snap-in
When it prompts you for local or remote server - put in the Host name of the server that you mapped to.
Tip: Windows uses established secure connection - if it can. Hence the map a drive trick work VERY well.
Please Note: I use this trick with WMI query(s) - hence the query never fails do to a timeout issue.
Joshua Flanagan outlined a process to delegate rights through modifying the security descriptor of the event logs.
Please add the domain user (without admin rights) to the "Event Log Readers" group on the target server. Then, from the source server, you can use the standard user credentials to access and read the event logs on the target.
If you could enable web access to the server then you could use an eventlog viewer page that I published a while ago. This would allow the administrators to run the website with just enough permissions to see the eventlog without granting you an account to login...

(IIS/Win2000Pro) Granting Registry read rights to IIS user?

Okay, so I'm running a small test webserver on my private network. I've got a machine running Windows 2000 Pro, and I'm trying to run an ASP.NET app through IIS.
I wrote it so that the webpage would use the registry to store certain settings (connection strings, potentially volatile locations of other web services, paths in the local filesystem where certain information is stored etc...) Of course, it worked fine when testing with VStudio.NET 2005, because the user running the app has elevated privileges. However, running it on IIS I get a "Access to the registry key 'HKEY_LOCAL_MACHINE\Software' is denied.", which suggests the IIS user doesn't have read access to that part of the registry (I only do reads through the website itself, never writes).
I was like "okay, simple enough, I'll just go give that user rights to that part of the registry through regedit." The problem is, I don't see an option anywhere in regedit to change security settings... at all. Which got me thinking... I don't think I've ever actually had to change security settings for registry hives/keys before, and I don't think I know how to do it.
Half an hour of searching the web later, I haven't found any usable information on this subject. What I'm wondering is... how DO you change security rights to portions of the registry? I'm stumped, and it seems my ability to find the answer on Google is failing me utterly... and since I just signed up here, I figured I'd see if anyone here knew. =)
If your having touble with RegEdit in Windows 2000 you can try the following:
Copy the Windows XP RegEdt32.exe to the Windows 2000 Machine
Using a Windows XP Machine, connect to the Windows 2000 registry remotely: File > Connect Network Registry
You can set permissions at the folder level for which you want to grant user permissions read/write access.
In your case, right click on the "Software" folder and select "Permissions".
You'll probably know the rest from there.
EDIT: If you still run into issues, you may want to modify your web.config file and use impersonation to have your web application run as a certain user account. Then you can put a tighter reign on the controls.
RegEdt32.exe will allow you to set permissions to registry keys.
Simply right click on a Key (Folder) and click Permissions, then you can edit the permissions as you would an file system folder.
I did so, assuming that a Security setting would be available. I didn't see any "Security" option when I right-clicked on the Key. =( I triple-checked just to make sure... and I just tried it on my XP machine, and it does indeed have the "Permissions" section... but the Windows 2000 machine doesn't. (how's that for wierd?)
In my searching, I found:
http://www.experts-exchange.com/Programming/Languages/.NET/ASP.NET/Q_21563044.html
Which notes that RegEdit for Windows 2000 doesn't have the Security/Permissions settings... but it proposes no solution to the problem. (Whoever asked the question was using Windows XP so he was okay... but in my case, it's 2000)
Is there any way to make it happen specifically in 2000?
EDIT: Ahhhh... if worse come to worse, I suppose I can do the impersonation as mentioned below... though if I can't set security settings for the registry in 2000, I'm left with making that user have Administrative access (I assume?) to actually get those rights, which sadly defeats the purpose. =(
Oh, let me try that! I didn't realize you could remotely connect to another registry.
(EDIT: I was wrong, it did work... it just took several minutes to respond to my request to change permissions remotely)
The remote connection idea did it! You're good! Thanks so much for your help! I never realized you could remote connect with RegEdit... you learn something new every day, they say! =) Thanks again for your assistance! =)
On another note though, about copying the XP version of RegEdit to Windows 2000... is that safe? I figured they would be coded in such a way as to be incompatible... but I could be assuming too much. =)
Just use RegEdt32.exe instead of Regedit.exe.
Go to the desired key or folder, then open the security menu and click on 'permissions'.

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