Hi @Anonymous ,
> This was working fine as of last Thursday but now seems to only affect Excel online which my company uses a lot
Are these links inserted into the Excel files?
Or do these links point to workbooks saved on clould, such as OneDrive, SharePoint or others? That you open these files in Excel app and find the wrong url?
Do you use a network proxy in company?
If yes, please temporarily disconnect for a test.
In addition, I find 2 similar thread you could have a look.
Recent (Sharepoint) Files which was opened local gets corrupted URL where %20 is replaced to %2520
Encoded URL's are Re-Encoded When Clicked
Any updates, welcome to share with us.
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