Exit code 3 error

Been running the .NET version for years. Switched to Azure hosting a year ago, and all was good as well for the site. We connect to a LOT of SFTP servers, and this has been very stable all along. Recently though we have been getting the following error:

WinSCP process terminated with exit code 3. There was no output. Response log file C:\Windows\TEMP\wscp1688.019FD045.tmp was not created. This could indicate lack of write permissions to the log folder or problems starting WinSCP itself.

There is no log created, and even when I enable logging this error does not log.

A reboot solves it for 3-4 days, but it comes back every time. Once it hits, then any further communcation is dead...and everything continues to fail until a reboot.

Our solution so far is to schedule daily reboots of the system, but today we got it in under a day!

Any ideas? On the latest .NET version. Manually running the .exe works fine. Server has no errors. Just the app.

Please enable debug logging (Session.DebugLogPath).
Also once the problem starts happening, check if there are any stale WinSCP processes. Or what is memory use.