Powershell and System.Security.Cryptography.X509Certificates.X509Certificate2 - security

Question

i'm getting this error when i run the system.security namespace. This is what i am running after
$cert=New-Object System.Security.Cryptography.X509Certificates.X509Certificate2("C:\mycert.cer")
New-Object: Cannot find type [System.Security.Cryptography.X509Certificates.X509Certificate2("C:\mycert.cer")]: make sure the assembly containing this type is loaded.
At line:1 char:19
+ $cert = New-Object <<<<
+ CategoryInfo : InvalidType: (:) [New-Object], PSArgumentException
+ FullyQualifiedErrorId : TypeNotFound,Microsoft.PowerShell.Commands.NewObjectCommand**
What am i doing wrong?

Answer 1

Try running this to see if you have the System.dll loaded (should be by default):
[AppDomain]::CurrentDomain.GetAssemblies() |
Where {$_.Location -match '\\System\\'}
If it is loaded then this command should show the X509Certificate2 type:
[AppDomain]::CurrentDomain.GetAssemblies() |
Where {$_.Location -match '\\System\\'} |
%{$_.GetExportedTypes()} | Where {$_.Name -match 'X509Cert'}
If the System.dll isn't loaded (which would be odd) try loading it:
Add-Type -AssemblyName System
See: http://technet.microsoft.com/en-us/library/hh849914.aspx

Answer 2

FYI ... I got error:
Unable to find type [System.Security.Cryptography.x509Certificates.X509Certificate2UI]
when using:
$certSelect = [System.Security.Cryptography.x509Certificates.X509Certificate2UI]::SelectFromCollection($certCollection, $title, $msg, 0)
However, I had no error creating the collection earlier on in my script:
$certCollection = New-Object System.Security.Cryptography.X509Certificates.X509Certificate2Collection
To make the error go away I had to include the following at some point earlier on:
Add-Type -AssemblyName System.Security

Answer 3

I've solved my problem. It's easily:
cd\
$cert=New-Object System.Security.Cryptography.X509Certificates.X509Certificate2("C:\mycert.cer")
cd\ is necessary

Answer 4

I ran into this in the ISE (but seems to apply to the normal command window too) and it seems that using autocomplete will automatically Add-Type for whatever you're looking for. If you start a new instance and run:
[AppDomain]::CurrentDomain.GetAssemblies() | grep Security
it will not return System.Security, but if you then type this and let intellisense do its thing:
[System.
You can then run this again:
[AppDomain]::CurrentDomain.GetAssemblies() | grep Security
And it will then return System.Security. So this is why you can write a script that works fine, and then revisit it later and it's broken. Using intellisense doesn't fix your script though, instead you have to add this line:
Add-Type System.Security
Or whatever library is not getting auto-added (it seems to need the dll filename, e.g. C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.6.1\System.Security.dll).
I'm pretty sure IseSteroids (a paid ISE add-in) can detect this, maybe others as well.