Hi @David Alridge
Microsoft Word HTTP 400 error when trying to insert a photo into a text box Does the photo come from online?
If yes, maybe a corrupt cookie or a big size cookie causes this issue.
please visit https://support.microsoft.com, click on the padlock at the left-hand end of the address bar to open the site info pop-up. Click on Cookies to reveal all the cookies that the site has set. Then select each cookie folder in turn and click Remove.
Besides, you may refer to Adrian P. G's last reply in thread 'Error in Word when trying to insert online picture.
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