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Outlook 365 has no functionality in Firefox.

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My university uses outlook 365. Today when I logged in to my email through my university's website and attempted to create an email message I noticed there were no functions available within the message, i.e. send, attach, etc... I did some research and deleted the cookies, and cleared the cache. That did not work. I reset Firefox and that did not work either. I even uninstalled and reinstalled Firefox and when I attempted to login in to outlook 365 after reinstalling Firefox I got the following error message and could not even log in to check my email: X-OWA-Error: ClientError;exMsg=Script error.;file=https://r4.res.outlook.com/owa/15.0.775.9/owa2/scripts/boot.1.mouse.js:0 X-OWA-Version: 15.0.775.9 X-FEServer: BL2PR03CA013 X-BEServer: null Date: 1/2/1601 2:16:37 PM I have no clue what this means.

My university uses outlook 365. Today when I logged in to my email through my university's website and attempted to create an email message I noticed there were no functions available within the message, i.e. send, attach, etc... I did some research and deleted the cookies, and cleared the cache. That did not work. I reset Firefox and that did not work either. I even uninstalled and reinstalled Firefox and when I attempted to login in to outlook 365 after reinstalling Firefox I got the following error message and could not even log in to check my email: X-OWA-Error: ClientError;exMsg=Script error.;file=https://r4.res.outlook.com/owa/15.0.775.9/owa2/scripts/boot.1.mouse.js:0 X-OWA-Version: 15.0.775.9 X-FEServer: BL2PR03CA013 X-BEServer: null Date: 1/2/1601 2:16:37 PM I have no clue what this means.

All Replies (1)

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Two other threads were posted recently indicating that the normal top bar was missing. One user said going into Firefox's full screen view (F11 key switches between normal and full screen views) would show the top bar, but that's inconvenient.

To help you get back in, can you try this from the login page: clearing your Firefox cache and deleting your saved cookies for the site.

(1) Bypass Firefox's Cache

Use Ctrl+Shift+r to reload the page fresh from the server.

Alternately, you also can clear Firefox's cache completely using:

orange Firefox button (or Tools menu) > Options > Advanced

On the Network mini-tab > Cached Web Content : "Clear Now"

If you have a large hard drive, this might take a few minutes.

(2) Remove the site's cookies (save any pending work first). While viewing a page on the site, either:

  • right-click and choose View Page Info > Security > "View Cookies"
  • Alt+t (open the classic Tools menu) > Page Info > Security > "View Cookies"

In the dialog that opens, you can remove the outlook.com cookies individually.

Then try reloading the page. Can you log in again?


Other Office 365 threads: