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When using firefox, I can't attach documents over 500kb to my outlook (OWA) emails.

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  • 2 have this problem
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  • Last reply by AliceWyman

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Recently I've noticed that I can no longer attach documents over ~500kb to my outlook (OWA) emails using mozilla firefox. When I attach smaller documents it works fine, but with bigger documents; I click "attach", select my file, and it appears on the email with a spinning wheel, but this doesn't change for several (>10) mins and then it says its failed to attach (or I give up and remove it). I've tried on Internet Explorer 11 and it works fine, so its not just an issue with OWA. I've also tried opening firefox in safe mode, but that didn't help.

Recently I've noticed that I can no longer attach documents over ~500kb to my outlook (OWA) emails using mozilla firefox. When I attach smaller documents it works fine, but with bigger documents; I click "attach", select my file, and it appears on the email with a spinning wheel, but this doesn't change for several (>10) mins and then it says its failed to attach (or I give up and remove it). I've tried on Internet Explorer 11 and it works fine, so its not just an issue with OWA. I've also tried opening firefox in safe mode, but that didn't help.

Chosen solution

Do you have Trusteer software installed? "Trusteer Rapport" or "Trusteer Endpoint Protection" is security software that some banks and other financial institutions recommend. Disabling it has been known to fix problems uploading large files or images using Firefox, as reported recently in these threads: https://support.mozilla.org/en-US/questions/1098352 https://support.mozilla.org/en-US/questions/1101495

If "Trusteer Rapport" or "Trusteer Endpoint Protection" software is installed you will see it listed on the Windows Start Menu "All Programs" list (ref.). If it's there, you can stop it from running and restart Firefox to see if that solves the problem. See this video if you need more help on how to temporarily disable this software.

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All Replies (3)

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Chosen Solution

Do you have Trusteer software installed? "Trusteer Rapport" or "Trusteer Endpoint Protection" is security software that some banks and other financial institutions recommend. Disabling it has been known to fix problems uploading large files or images using Firefox, as reported recently in these threads: https://support.mozilla.org/en-US/questions/1098352 https://support.mozilla.org/en-US/questions/1101495

If "Trusteer Rapport" or "Trusteer Endpoint Protection" software is installed you will see it listed on the Windows Start Menu "All Programs" list (ref.). If it's there, you can stop it from running and restart Firefox to see if that solves the problem. See this video if you need more help on how to temporarily disable this software.

Modified by AliceWyman

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Thank you for your reply. Yes I do in fact have Trusteer software installed on both my work and home computer because it's recommended (essential even) for some of my online banking.

I have tried disabling Trusteer software and that has solved the problem, but for security I will re-enable Trusteer and use Safari instead for uploading data.

This problem I first noticed back in October and I'm amazed that Trusteer have not yet fixed it (I presume it's down to them).

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If anyone needs to have Trusteer software working with Firefox, please contact their support site. You can use this link: https://www.trusteer.com/support/submit-ticket

I'll close this thread.