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Forum Discussion
Issue with Excel - "Excel file format is not valid"
Excel file format is not valid. Please help as unable to open Excel.
I think I found the solution.
If you disable the office dropbox add-in the problem doesn't seem to occur anymore. You can still save to dropbox via file explorer making it redundant anyhow.
to do this, open excel, go under file, Choose "Options", and navigate to "add-ins".
From there locate the Dropbox Add-in and right click, select "disable".
Should stop it from being an issue.
Rich
Super User II
Super User IIYou need to provide more information about the problem you're having. Are you opening Excel files from the Dropbox folder on your desktop, or the Dropbox website? Does the problem only occur with files in your Dropbox folder, or elsewhere on your computer as well? Have you dragged one of the problem files out of your Dropbox to your desktop and tried to open it from there? Mac or PC? Office version? etc.
The issue happens when a user uses the dropbox office 2016 add-on to do a save as function in excel 2016 directly into dropbox.
Example: Someone sent me a .csv I open it in excel 2016 but would prefer it be saved as .xlsx . If I choose save as the dropbox option is displayed at the left. with the add-on. If you select this and change the file format it saves to dropbox in the original format and only changes the file extension. Causing the file to appear corrupted. If you do this process in any other way either with competing cloud storage or just through file explorer it is fine and works as expected.
That is the nature of the issue. Noted in windows 7, windows 8, and windows 10, excel 2016 365.
Example: Someone sent me a .csv I open it in excel 2016 but would prefer it be saved as .xlsx . If I choose save as the dropbox option is displayed at the left. with the add-on. If you select this and change the file format it saves to dropbox in the original format and only changes the file extension. Causing the file to appear corrupted. If you do this process in any other way either with competing cloud storage or just through file explorer it is fine and works as expected.
That is the nature of the issue. Noted in windows 7, windows 8, and windows 10, excel 2016 365.
