Is it possible to turn off drag and drop functionality when users create new versions of a document?

Unfortunately I don't think this is currently possible. M-Files asks for a confirmation when a user does this so they shouldn't be able to replace the file by accident.

It's not about replacing by accident. The issue is that users can drag and drop any file from their desktop onto a specific document in M-Files and over-write it with a new version. For example, we save piping drawings as PDF files. Sometimes we have multiple people that need to markup changes on that PDF(usually using Bluebeam). One user makes a copy of the document that they save on their desktop and they make markups. A 2nd user checks out the document and makes changes and then checks in the document. The first user now has an old version of the drawing document on their desktop where they make markups on and then drag and drop that file into M-Files. Now we have a version that doesn't show user 2's changes in the most recent version.

To eliminate this potential issue we thought removing the drag and drop option, but only when adding additional versions of an existing document, not for the creation of a new document object.

Another option we have considered is co-authoring, but this seams o only work with Word, Excel, and PowerPoint.

Sounds to me like "user makes a copy of the document that they save on their desktop" is the main problem here. Everyone should be working on the document in M-Files so that there's only one copy and everyone sees the latest version which can be reserved for editing.

Part of the solution may be user training and guidance, but you may also want to raise this with your M-Files representative to check if there would be some configurations that would help here. Perhaps you can restrict creating external copies in the first place if that's not otherwise required by your processes?

The official co-authoring options in M-Files are for Microsoft Office files, but it might be possible to develop a custom co-authoring solution with some third-party service if that would streamline your collaboration. Again, this is something best discussed with a representative who understands your use cases and operations as a whole.

Sounds to me like "user makes a copy of the document that they save on their desktop" is the main problem here. Everyone should be working on the document in M-Files so that there's only one copy and everyone sees the latest version which can be reserved for editing.

Part of the solution may be user training and guidance, but you may also want to raise this with your M-Files representative to check if there would be some configurations that would help here. Perhaps you can restrict creating external copies in the first place if that's not otherwise required by your processes?

The official co-authoring options in M-Files are for Microsoft Office files, but it might be possible to develop a custom co-authoring solution with some third-party service if that would streamline your collaboration. Again, this is something best discussed with a representative who understands your use cases and operations as a whole.