Reader DC Checking-in files to SharePoint

Hello,

we have been using Adobe Reader DC to connect to our Sharepoint sites, check-out, modify and check back in PDFs to Sharepoint libraries.

This has suddenly started resulting in the below error when checking the document back in, the strange thing is that it doesn't appear to matter which PDF we use but it does seem to work correctly on some Sharepoint sites but not others.

The error from the application suggests an issue with SharePoint rather than the application, so any help tracing how I can narrow down the problem would be much appreciated. I initially contacted Microsoft to discuss this. However they have done some testing and found the same error at their end, they have directed me to Adobe as they believe the issue is with Reader rather than SharePoint.

Error when checking a document back in: "File check in failed. the server said the operation failed because an unexpected error occured. (Result Code: 0x80020005)"

We are using Reader version 2019.012.20035

Many thanks