Excel HTTP Error 400. The size of the request headers is too long

Anonymous
2024-01-25T17:23:24+00:00

Good afternoon,

Today I was helping a user, Alice, change a picture in the header of an excel workbook. When Alice clicks the "picture" button in the ribbon under the "Header and footer" tab, instead of showing the dialog to pick a file to insert, the window that pops up says "HTTP Error 400. The size of the request headers is too long" with no other information.

Notably, if Bob, another user with an apparently identical account and user profile, tries to follow the same steps on the same computer as Alice, Bob is able to do so without receiving the error message.

We have tried the following:

Reinstall office365

Sign out of user account and back in

Split the document into smaller documents in case it was a file size issue

Running the repair tool for office365

Thank you!

Edit:

Good morning! I am happy to say we found a solution! Unfortunately it was to reinstall Windows.

Microsoft 365 and Office | Excel | For business | Windows

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Anonymous
2024-02-01T11:11:15+00:00

Good afternoon,

Today I was helping a user, Alice, change a picture in the header of an excel workbook. When Alice clicks the "picture" button in the ribbon under the "Header and footer" tab, instead of showing the dialog to pick a file to insert, the window that pops up says "HTTP Error 400. The size of the request headers is too long" with no other information.

Notably, if Bob, another user with an apparently identical account and user profile, tries to follow the same steps on the same computer as Alice, Bob is able to do so without receiving the error message.

We have tried the following:

Reinstall office365

Sign out of user account and back in

Split the document into smaller documents in case it was a file size issue

Running the repair tool for office365

Thank you!

the following solution is also possible:

file - account - settings management - turn off optional online functions and done

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  1. Anonymous
    2024-03-16T00:21:28+00:00

    Muito obrigado! Consegui resolver o meu problema com a sua resposta

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  2. Anonymous
    2024-03-14T18:05:13+00:00

    BRILLIANT! Thank you- this worked for me too.

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  3. Anonymous
    2024-02-25T19:17:52+00:00

    Looks like this solution no longer works. :(

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  4. Anonymous
    2024-01-25T18:26:18+00:00

    I forgot to mention it originally but I did follow the steps laid out in that article. We even tried reinstalling Chrome on the off chance that would help.

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