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Unable to load Javascript in OWA

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Hello, I am unable, for the past 2 days, to load my webmail from Outlook.com (outlook.live.com/mail) and my outlook calendar online (outlook.live.com/calendar), but have no problem to access OneDrive and my other MS apps. I get in both cases a "failed to load Javascript" error messages, failing to load the "chunk 5016797" in mail, and the "chunk 917352" in calendar. Refreshing the tabs, restarting FF, restarting the computer, restarting FF in troubleshooting mode (no extensions) as suggested in an existing thread on this topic, updating FF and updating Windows (still Win8.1, though), didn't help. I access normally both mail and calendar in Chrome, but want to keep and use FF as my main browser. Can you help fixing this JS issue ? Many thanks

Hello, I am unable, for the past 2 days, to load my webmail from Outlook.com (outlook.live.com/mail) and my outlook calendar online (outlook.live.com/calendar), but have no problem to access OneDrive and my other MS apps. I get in both cases a "failed to load Javascript" error messages, failing to load the "chunk 5016797" in mail, and the "chunk 917352" in calendar. Refreshing the tabs, restarting FF, restarting the computer, restarting FF in troubleshooting mode (no extensions) as suggested in an existing thread on this topic, updating FF and updating Windows (still Win8.1, though), didn't help. I access normally both mail and calendar in Chrome, but want to keep and use FF as my main browser. Can you help fixing this JS issue ? Many thanks

All Replies (3)

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I sorted the issue out, by deleting the browser cache, and logging out of my two outlook accounts, a few days later. However, as of 17 May, I again have the same issue (combining chunk moad issues #501697 and 414284), and refreshing, troubleshooting, restarting, updating Java, as previously, failed to solve the issue. I do not have that problem in Chrome, however and unlike FF, Chrome has stopped updating because I am stuck with Win8.1... Any suggestions welcome,

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If you use extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) that can block content (Adblock Plus, NoScript, DuckDuckGo PE, Disconnect, Ghostery, Privacy Badger, uBlock Origin) always make sure such extensions do not block content.

Firefox shows a purple shield instead of a gray shield at the left end of the location/address bar in case Enhanced Tracking Protection is blocking content.

  • click the shield icon for more detail and possibly disable the protection

You can check the Web Console for relevant-looking messages about blocked content.


You can try these steps in case of issues with webpages:

You can reload webpage(s) and bypass the cache to refresh possibly outdated or corrupted files.

  • hold down the Shift key and left-click the Reload button
  • press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
  • press "Command + Shift + R" (Mac)

Clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Settings).

"Remove the Cookies" for websites that cause problems:

  • Settings -> Privacy & Security
    Cookies and Site Data: "Manage Data"

"Clear the Cache":

  • Settings -> Privacy & Security
    Cookies and Site Data -> Clear Data -> [X] Cached Web Content -> Clear

Start Firefox in Troubleshoot Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or if userChrome.css/userContent.css is causing the problem.

  • switch to the Default System theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Troubleshoot Mode start window

You can remove all data stored in Firefox for a specific domain via "Forget About This Site" in the right-click context menu of an history entry ("History -> Show All History" or "View -> Sidebar -> History").

Using "Forget About This Site" will remove all data stored in Firefox for this domain like history and cookies and passwords and exceptions and cache, so be cautious. If you have a password or other data for that domain that you do not want to lose, make sure to backup this data or make a note.

You can't recover from this 'forget' unless you have a backup of involved files.

If you revisit a 'forgotten' website, data for that website will be saved once again.

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Thank you for your prompt reply, which I will keep. The OWA mail is back working withouth having to try any of your checks. I keep them for the future, especially how to use cache, cookies data, and the troubleshooting shortcuts.