Thank you for voting for “there’s a problem with the clipboard” issue. I think this refers to this error dialog: “There’s a problem with the clipboard, but you can still paste your content within this workbook."
When Excel shows this dialog after a copy (CTRL+C) action, it means that another app has a lock on the system clipboard. In this situation you can still paste within Excel. However you cannot paste to another app like Word or Outlook which uses the clipboard.
A while ago we made some improvements for Office365 users so that this error message only shows once per Excel instance. This was based on customer feedback – the design change prevents it popping up multiple successive times when the clipboard is locked. We have also considered never showing the error dialog, but there was user feedback that this message is informative and helpful in some cases.
An error occurred while saving the commentNate commented
I also see this continuously. Even with the feature where one drags the cell to copy it. I get a warning that the clipboard is full even if I just cleared it. I agree with the Stephen Goodman comment Nov 26 2018, Excel is in conflict with itself. This conflict effectively removes the drag-cell-to copy feature. I find the only solution is to "cut" and "insert cut cells" to obviate this issue. Please look into this. I have no perspective on when this was introduced. This is an issue on my personal Office 365 account and the Office Standard 2106 product.