Cannot upload file: Unknown server error (404)


for some unknown reason, we cannot upload files larger than approximately 26 mb in size to our JIRA instance. Our max attachment size is 100 mb, and the server storage size is 300+ gb.

We can upload files <25 mb without any issues at all, but as soon as you break that 25-26 mb boundry it throws that error in the subject line.

I cannot peg the source.

We're running a stand alone.

Windows Server 2008 R2 6.1

App container; Apache Tomcat/7.0.29

JIRA version 6.0.0

Any help is appreciated.



3 answers

Hi Adam

After making the change in the attachment size as set in this documentation:

You need to restart your instance to make the changes replicate.


Ricardo Carracedo.

Hello Ricardo,

I just restarted the instance, it made no difference. :(

Thanks for trying.


Hey Adam,

if you are behind a proxy you should configure the max allowed size of attachments.


No, we're sitting inside the same network firewall as the instance.

It appears there was a session limit by default within IIS7 which was set to 30,000,000 bytes. We ameneded this so that we could upload files up to 100mb in size and it now works fine.

Thanks all for the help.

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