If you’ve seen a similar notification, I empathize with your pain. I don’t know that there is one solution to this problem, either, so I’m going to share a number of them we’ve used and hope that one (or all) of them will help you.
Basically a file is added through file explorer (a cloud library in OneDrive or SharePoint being synced locally to your computer) but then after a moment a notification appears which says “You now have two copies of a file; we couldn’t merge the changes in [filename]” and then the filename is appended with your computer name again and again until eventually the filename is too long and is harder to delete. Let’s not get to that point.
Two issues we’ve found:
- File Size
- SharePoint Workflows
We’ve only run into this issue when the file in a frenzy is significant in size. Due to that size, and multiple people syncing the same library, I imagine it’s pinging back and forth as it downloads, copies, uploads, discovers a conflict, downloads, copies, etc. And many of the files you’re left with will oddly be corrupt 0 KB files. It becomes a bit of a game to try to actually delete the files, but I would suggest trying to delete the file from the browser, and not file explorer so you catch it upon creation and not after download. We eventually used workflow to help us delete any files created or changed with ComputerName-ComputerName-ComputerName in the title because if you’re not fast enough, the process will just continue its copy, download, upload cycle.
As for workflows, we noticed if we turned off workflows on the document library in question, we didn’t get the same issue. A workflow was trying to modify the large file while it was being downloaded through everyone’s sync client so it encountered a sort-of “save conflict” while syncing both ways. But, unfortunately, we needed the workflow more than we needed the convenience of easy uploads.
So, currently, our workaround for large files is to upload them via the browser, not file explorer. You can still edit and access the large files through file explorer just fine, but when you first add them, add them via your browser with drag-and-drop or the upload button. This way you can keep your workflows as they are and avoid the never-ending cycle of terror…I mean error.
Here are three other things you can try:
- Delete multiple versions of Office. For example, if you have Microsoft Office 2010 and 2016 on your computer, uninstall 2010.
- Click Start –> Settings –> Apps –> Microsoft Office (older version)
- Click uninstall on the old version and follow prompts
- Restart computer
- Repair your Office programs (make sure they’re up-to-date)
- Click Start –> Settings –> Apps –> Microsoft Office
- Click “Yes” if asked to make changes to computer
- Click Quick Repair –> Repair
Note: Try Online Repair instead if you wish – this is basically like re-installing the programs and takes a while.
- Have everyone syncing that library delete their Microsoft Upload Center cache.
- Click Start –> Microsoft Office –> Office Upload Center
- Click Settings
- Delete cached files
And if none of those work, your other option is to have users stop using the sync client altogether for that library. Here’s how to stop syncing a library:
- Right-click the OneDrive icon in your system tray
- Click settings
- Under the “Account” tab, click “Stop Sync” next to the problem library, “Stop sync” again in the dialog to confirm, then OK