Hi Rich,
I understand that "Check In" button is grayed out when you check out a document with or without changes to the checked out document. To narrow down the root of the issue, I’d like to collect the following information:
1.Does this happen to the Office files besides Adobe Illustrator .ai files?
2.Does this happen to all the user in your company?
3.Could you check whether the file is checked out on your SharePoint site when you check out the file on Document Connection?
4.Where do you download MS Doc Connection for Mac 14.3.7?
Please let us know the detailed information so that we can help.
Thanks,
Kevin Hu