Hi Rick, you may be experiencing SPR 933190 - Customer just upgraded from 2014 SP5 to 2016 SP1 and users are now unable to release their PDF files to the workflow when updating version free variables on the PDF card. Issue affects PDF files since EPDM 2016 introduces a PDFPlugin. The version free variable updates a checked in, read-only file - but the PDF file format plugin is likely trying to write to the file even though there is no mapping in the version free variable and fails with 'file is open' error.
This is the workaround suggested in the KB:
Workaround: This workaround will disable the PDF custom property mapping, but allows updating the version free variable without error 1. Open regedit and browse to: HKEY_LOCAL_MACHINE\SOFTWARE\SolidWorks\Applications\PDMWorks Enterprise\FileFormats\.pdf 2. Delete the registry value '8' (linked to pdfplugin.dll) 3. Kill and restart explorer.exe process.