C# Only part of a ReadProcessMemory or WriteProcessMemory request was completed during Process.Kill()

Question

I have been researching this issue pretty extensively and cannot seem to find an answer.

I know that the Only part of a ReadProcessMemory or WriteProcessMemory request was completed exception is thrown when a 32-bit process tries to access a 64-bit process and the same for a 64-bit modifying a 32-bit process.

The solution to that issue is to change the Platform Target to 'Any CPU'. I have tried this and unfortunately this does not solve my issue.

The next block of code is what keeps throwing the exception. The program that runs this code is used to open up applications on remote computers and keeps a list of all the processes that the program itself opened so that I don't have to loop through all the processes.

Process processToRemove = null;
lock (_runningProcesses)
{
    foreach (Process p in _runningProcesses)
    {
        foreach (ProcessModule module in p.Modules)
        {
            string[] strs = text.Split('\\');

            if (module.ModuleName.Equals(strs[strs.Length - 1]))
            {
                processToRemove = p;
                break;
            }
        }
        if (processToRemove != null)
        {
            break;
        }
    }
    if (processToRemove != null)
    {
        processToRemove.Kill();
        _runningProcesses.Remove(processToRemove);
    }
}

These processes can and most likely will be 32-bit and 64-bit, mixed together.

Is there anything I am doing that I shouldn't be doing, or is there just a better way to do all of this?

Answer 1

As detailed in the comments of the MSDN page for Process.Modules and this thread there is a known issue in Process.Modules when enumerating 32 bit processes from a 64 bit process and visa-versa:

Internally .NET's Process.Modules is using function EnumProcessModules from PSAPI.dll. This function has a known issue that it cannot work across 32/64 bit process boundary. Therefore enumerating another 64-bit process from 32-bit process or vice versa doesn't work correctly.

The solution seems to be to use the EnumProcessModulesEx function, (which must be called via P/Invoke), however this function is only available on later versions of Windows.

We fixed this issue by adding a new function called EnumProcessModulesEx to PSAPI.dll (http://msdn2.microsoft.com/en-us/library/ms682633.aspx), but we currently cannot use it in this case:

• it only works on Windows Vista or Windows Server 2008
• currently .NET 2.0 Framework don't have a service pack or hotfix to make Process.Modules use this new API