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Hi,
I have http error 400 pop up on my screen when trying to download attachments. I cannot refresh my screen and have to restart my computer to close outlook.
Troubleshooting browser crashes or performance issues on Windows 11
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(131.20000000000002, 8%, 22%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EPB%3C/text%3E%3C/svg%3E)
I am experiencing the same issue. I only use the Outlook for Windows which does not seem to have a way to not use another browser than edge. Issue seems to have arisen in the past 2 days.
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(92.8, 53%, 18%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EGS%3C/text%3E%3C/svg%3E)
Hi,
I have several user presenting the same issue. We're using the New Outlook for Windows and always happens when they try to open an attachment. I've instructed them to download that attachment and open the file as a workaround.
I can preview the attachment, its when I go to save the file that I get the http 400 error.
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(169.60000000000002, 77%, 26%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EKJ%3C/text%3E%3C/svg%3E)
Hi,
May I ask if this happens when you try using InPrivate or another browser?
Does this only happen when you download an attachment from the Outlook.com website?
Does this happen if you use New Outlook for Windows or the Outlook mobile app?
Also, please disable any extensions, 3rd-party anti-virus app, and any software connected to your browser.
The above questions are to isolate the cause of the issue. Please let me know how it goes. I look forward to your response.
Stay Safe!