Checking Who has an Excel File Open In Powershell - excel

Question

Im using Powershell 4.0 on win7 64 bit, I want to see who has an excel file open, or even if the file is open.
Example. I have the excel file "test" on network drive B. If one person opens "test" I understand that will create an excel lock file looking like this "~$test.xls".
So far I have used Test-path to verify that the excel lock file exists. Then I believe I can use Get-Acl to find the owner of that file. Is there a simpler way to find out who has an excel file open? Or will my workaround for checking the ownership of the lock file work?

Answer 1

I still use Netapi32 based functions for achieving this.
Add-Type -TypeDefinition #"
using System;
using System.Runtime.InteropServices;
public class Netapi
{
[DllImport("Netapi32.dll",CharSet=CharSet.Unicode)]
public static extern int NetApiBufferFree(IntPtr buffer);
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct FILE_INFO_3
{
public uint FileID;
public uint Permissions;
public uint NumLocks;
[MarshalAs(UnmanagedType.LPWStr)] public string Path;
[MarshalAs(UnmanagedType.LPWStr)] public string User;
}
[DllImport("Netapi32.dll",CharSet=CharSet.Unicode)]
public static extern uint NetFileEnum(
[In,MarshalAs(UnmanagedType.LPWStr)] string server,
[In,MarshalAs(UnmanagedType.LPWStr)] string path,
[In,MarshalAs(UnmanagedType.LPWStr)] string user,
int level,
out IntPtr bufptr,
int prefmaxlen,
ref Int32 entriesread,
ref Int32 totalentries,
ref Int32 resume_handle);
}
"#
function Get-OpenFiles
{
[CmdletBinding()]
param ( [string]$Server = "localhost",
[string]$User = $null,
[string]$Path = $null)
$struct = New-Object netapi+FILE_INFO_3
$buffer = 0
$entries = 0
$total = 0
$handle = 0
$Level=3 # used to define the type of struct we want, i.e. FILE_INFO_3
$ret = [Netapi]::NetFileEnum($server, $path, $user, $level,
[ref]$buffer, -1,
[ref]$entries, [ref]$total,
[ref]$handle)
$files = #()
if (!$ret)
{
$offset = $buffer.ToInt64()
$increment = [System.Runtime.Interopservices.Marshal]::SizeOf([System.Type]$struct.GetType())
for ($i = 0; $i -lt $entries; $i++)
{
$ptr = New-Object system.Intptr -ArgumentList $offset
$files += [system.runtime.interopservices.marshal]::PtrToStructure($ptr, [System.Type]$struct.GetType())
$offset = $ptr.ToInt64()
$offset += $increment
}
}
else
{
Write-Output ([ComponentModel.Win32Exception][Int32]$ret).Message
if ($ret -eq 1208)
{
# Error Code labeled "Extended Error" requires the buffer to be freed
[Void][Netapi]::NetApiBufferFree($buffer)
}
}
$files
}
Then you can call the Get-OpenFiles and pass a specific path name:
Get-OpenFiles -Path C:\Temp\EXCEL.XLSX
FileID : 205
Permissions : 35
NumLocks : 0
Path : C:\Temp\EXCEL.XLSX
User : mickyb
Using Get-OpenFiles -Path C:\Temp works too:
FileID : 205
Permissions : 35
NumLocks : 0
Path : C:\Temp\EXCEL.XLSX
User : mickyb
FileID : 213
Permissions : 51
NumLocks : 0
Path : C:\Temp\~$Excel.xlsx
User : mickyb
You could also see if a specific user has files open:
Get-OpenFiles -User mickyb

Answer 2

If you copy the contents of the lock file to the console it should contain the name of the user who has the file locked. You may have to make a copy of the lock file in order to read it. I'm not familiar with PowerShell but I assume it has all the power of DOS batch files and a technique similar to what I wrote below could be created.
Here is a batch file I have added to my SendTo folder which allows me to right-click on an Excel file and it will show me who has the file locked. I have tested this with .xlsx and .xlsm files.
#echo off
REM ===================================================================
REM Put this in your SendTo folder and it will let you right-click
REM on an .xlsx/.xlsm file and show you the user name in the lock file
REM
REM If an Excel file is locked, look to see if a hidden lock file exists. If
REM the file is found, make a local temp copy of it and display the contents which
REM should be the name of the user holding the lock.
REM ===================================================================
setlocal
set file="%1"
REM Make sure the file has a compatible extension.
if "%~x1"==".xlsx" goto :ExtensionIsValidExcel
if "%~x1"==".xlsm" goto :ExtensionIsValidExcel
echo.
echo "%~n1%~x1" is not a supported file type.
echo.
pause
exit
:ExtensionIsValidExcel
REM If an Excel file is locked, look to see if a hidden lock file exists. If
REM the file is found, make a local temp copy of it and display the contents which
REM should be the name of the user holding the lock.
IF EXIST %~dp1~$%~n1%~x1 (
ECHO f | Xcopy %~dp1~$%~n1%~x1 "%TEMP%\~temp.txt" /H /R /Y /F
attrib -h -s %TEMP%\~temp.txt
cls
ECHO.
ECHO The Excel file "%~n1%~x1" file is locked by:
ECHO.
REM copy the file to the console to show the user name.
copy %TEMP%\~temp.txt con | Find /v "file(s) copied"
del %TEMP%\~temp.txt
) Else (
cls
ECHO.
ECHO The Excel file "%~n1%~x1" file is not locked in a way this was expecting.
)
ECHO.
ECHO.
pause