Excel cannot open the file ...xlsb because the file format or extension not valid - error for few users for couple files while same files work fine for other users.

Question

Excel cannot open the file ...xlsb because the file format or extension not valid - error for few users for couple files while same files work fine for other users.

Anonymous

Hi Team,

We are facing peculiar issue with .xlsb macro files. Most of the users in the company have been using .xlsb/.xlsm files for quite some years. From last one month, only few users are receiving the error "Excel cannot open the file 'filename.xlsb' because the file format or extension not valid. Verify that the file has not been corrupted.. " only on couple of files. Same files which were working fine few weeks back are giving the error on opening them.

Our machines have Win 11 with One Drive set up. Office Application is 365 Apps for enterprise. Files are available locally on the drive as well. This issue is not limited to any one region either.

Solutions tried so far:

We have tried deleting cached/temp files. For one of the users after deleting temp files - the file worked for few hours. After restart/next day again he started receiving the same error.

If we save the .xlsb as .xls file can be opened - but that is destroying the files logic/formulae [due to limited number of rows/cols in 2003 excel].

We are working with company IT team. In the meanwhile, has anybody faced this issue. Could it be user profile issue or some app version/os combination issue? Has there been new update pushed to One-Drive/Office Apps or to OS that might be creating this issue?

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Answer accepted by question author

7 additional answers

Answer 1

We finally found a solution. Looks like the issue was due to tighter security rules by the IT Security team that restricted certain users from opening the .xlsb files.

But it's strange that it impacts only certain users. To mitigate the issue, IT Team had to create a new AD Security group and add the Device Name of affected users to that group.

Thanks for the support.

Answer 2

Anonymous

Thanks for the suggestion. But this did not work. :(

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Answer 3

Anonymous

You may try removing this folder from register editor. It will recreate automatically at next time when you open Excel.

Removing this folder will reset all the Excel settings.

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Answer 4

You may try putting the file to local instead of OneDrive for testing if issue can be reproduced.

It could be bug that something in file is removed when file is in OneDrive.

Could you also share us a test file to reproduce your issue? Then we may help you determine the cause of it.

For sharing a sample workbook, upload to OneDrive or any other cloud drives. Then post a link here.

Thanks for the reply! I did try opening it from the C: - outside of OneDrive, it didn't work.

Sorry, I'll not be able to share the file as the macro works with company data and business logic.

PS: Files work just fine for me/my team even now. Issue is among the users of our files, only few of them are facing this issue. Even if I provide them a fresh copy of the file from my machine - they still get the error. All these files were working fine on their machine earlier.

Answer 5

You may try putting the file to local instead of OneDrive for testing if issue can be reproduced.

It could be bug that something in file is removed when file is in OneDrive.

Could you also share us a test file to reproduce your issue? Then we may help you determine the cause of it.

For sharing a sample workbook, upload to OneDrive or any other cloud drives. Then post a link here.

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Excel cannot open the file ...xlsb because the file format or extension not valid - error for few users for couple files while same files work fine for other users.

7 additional answers