File download problem

[The_Owle]

Users of my web site, running MD-Pro, a PostNuke (php-based) clone, started to report difficulties downloading files from the download module. We assumed it was the download module and spent ages diagnosing it, uploading fresh versions etc. After some time someone had the bright idea to see if the files could be downloaded direct (using the URLs) to eliminate the web application.

We found:


Some users can download all files from the server with no problems.
Some users can download some files but not others.
The files on the server are not corrupted and there are no permissions issues.
Disabling antivirus and firewalls locally makes no difference.


Platforms include Mac, Windows and Linux and browsers include IE7, Firefox and Safari.

The only common element I can see is that the ony files causing trouble are MS Word, though some of these do download OK


The download problem seems sometimes to be that the server does not respond at all, sometimes that the file starts to download and then stalls before completion. The browsers never seem to time out - they wait indefinitely.


We have run out of ideas why this should be happening. How can some users have problems with the same files on the same server and others not?

Help please!!!

[degsy]

Welcome :)

Check your server logs to see what is happening at the time

[The_Owle]

Thanks. We have been working on this and we have now discovered that files in the web root are OK. The furhte down the directory structure they are, the less likely they are to download. Performance varies according to the browser in use. According to the host technical support, 'Firefox appears to be returning the data from its own cache. IE is only doing so for root. For the other places IE tries to download the file but stops receiving at exactly the same number of bytes from different locations.'

Another odd feature is that so far it seems that only MS Word files are affected. OTher doc types weem to be OK. We're still baffled.

[degsy]

Does your server have any cache management operating?
How about your ISP?

Are you downloading the files directly or using a download manager script?
Have you got cache prevention code in your script?

[The_Owle]

This problem has now been solved. The unexpected solution may be of interest to other users. Here is the comment from the web host:

I'm SO glad this is finally fixed!! Wow. Well, this was really the last resort - we'd tried everything else we could, firewalls, file types, mimetypes. There was no bug in the Apache bugzilla either open or closed that matched what we were experiencing however there was one bug related to MS-Word documents so I figured it was worth a try, I'm so glad I did!
According to my email client you've sent 59 emails regarding this matter, implying I've sent 59 back - 118 emails, I think this would rank as the 2nd largest support ticket in [our] history (the other one was simply ridiculous)!
I'll update Apache on our other servers now, just in case someone else runs into this problem. Thanks for helping in getting to the bottom of this very tricky issue!

Thanks for the replies, and I have to give a pat on the back to www.nethosted.co.uk for their fantastic support.

[degsy]

Thanks for the update :)