Windows Defender Antivirus real-time protection slows down Acrobat Distiller

I just had this issue happen here, too. It took me almost two days to figure out what the culprit was. This is FrameMaker 2015 (patch5) on Windows 10 Pro, version 20H2:

I was trying to save different files and books to PDF, and had to force quit FrameMaker after every single attempt because - other than a permanently spinning hourglass/wheel - nothing happened. FrameMaker did not save a PDF file, did not create a *.tps file, and did not give any error message, for a very long time (I've waited for more than an hour once). Nothing happened, actually, apart from FrameMaker apparently freezing.

I did a few tests with newly created and more or less empty pages (just a few words), which could successfully be saved to PDF. So I started to inspect the graphics used in the regular files, if those could cause issues. Another few hours later I knew that the kind or details of graphics were not the issue. It was simply the presence of (pixel) graphics which prevented the PDF files from being saved.

I started watching the save-to-PDF event in the Windows task manager. There, during attempted PDF creation,  I found a system idle process (94%) and MsMpEng.exe (6%). Without having started a PDF creation in FrameMaker, there was only the system idle process (99%). The above happened reproducibly. Start saving a PDF, and the MsMpEng.exe goes to 6%. Googling this exe showes it belongs to Windows Defender. Obviously each time I started saving a PDF, Windows defender intercepted the data stream which should be written to file (tps) and inspected it for virus activity, which brings the whole PDF creation process to a grinding halt.

Windows defender allows to set exclusions. First I tried to exclude the drive (folder) to which the files were written, but this did not change anything. Then I excluded the process "FrameMaker.exe"… bingo. This solved it. From hours of spinning hourglasses back to a few minutes, including the regular events like writing and later deleting a *.tps file.

This seems to be a Windows 10 thing, and maybe only specific versions. We have several FrameMaker 2015 installations in Win7 VMs which work reliably and without any problems. And I already had created PDFs with this Windows-10 based FrameMaker installation before, without problems. This all started after the (recently performed) update to 20H2.

Just in case anybody else encounters such problems with saving PDFs: There's a solution. However, I don't quite understand how that problem started in the first place… must be something in the last Windows update.

Bernd

I wonder if this is a temporary escalation of AV defenses in the wake of the on-going SolarWinds attack. Any app that phones home might be considered suspect, until all the facts are in. If any party was an SW client, their apps might be under greater scrutiny even if all they do is auto-update from time to time. Alas, MS itself is an SW client. The trade press reports that the SW software itself was still relying on Flash.