Errors when creating multiple PDF's in succession. Unable to find "Adobe PDF" resource files.

[Brian5DC4]

When creating multiple PDFs in succession, I encounter the error:

Unable to find "Adobe PDF" resource files.

"acrobat.dll\AMT\"

Selecting OK closes the error. The error comes up next. 

"Error registering Distiller window class. Another copy of Acrobat Distiller may already be running. Error: 1410 - Class already exists."

Clicking the "OK" clears and processing resumes.

What are possible cause of this?

THank You

[Test Screen Name]

Are you running everything in an interactive session, as the normal logged in user (no background tasks, not an elevated process, not a service etc.)?

If so, you probably need to serialise more carefully. You MUST NOT use the Adobe PDF printer nor Acrobat Distiller simultaneously from more than one process or thread.