We have several existing workflows and none of them are running. They give the error, "Failed on Start workflow was cancelled by System Account".
We are able to create a new simple workflow with no conditions and it will run but any with conditions will not.
We found posts referring to giving full control to the system account to the Windows\temp directory. I gave that account Modify permission and that didn't fix the issue.
We can't create new workflows with conditions either so another post mentioned to delete the Sharepoint Designer cache and remove the files under the %USERPROFILE%\AppData\Local\Microsoft\WebsiteCache and %APPDATA%\Microsoft\Web Server Extensions\Cache directories. This also didn't fix the problem.
There are no meaningful entries in the event viewer or the Sharepoint logs.
Does anyone have any ideas on what to check next?