MobilePress caused 55,000+ files in c:\windows\temp

March 19th, 2009 by jason Leave a reply »

A while after installing the MobilePress 1.0.3 plugin for WordPress, my IIS server locked up.  I rebooted it and all was well.  A while later, it locked up again.  Upon further investigation, I found 55,000+ files in the c:\windows\temp\ folder and new files were popping in there at a rate of a few per minute.

Each of the 55,000 files looked like:




where the prefix of sess_ is common but the rest is random.

Using Sysinternals procmon.exe, I was able to identify right away that the process responsible for creating the files was w3wp.exe which pointed me to IIS.  However, I wasn’t sure why IIS would begin doing this after being stable for a long time.

Searches on the internet said the files were being generated by PHP and indicated new user sessions as visitors hit my blog.  That helped confirm the fact that these were coming from IIS and the blog but still no tell tale reason as to why all of the sudden.

Then I opened up one of the files and it showed:

That was enough to jog my memory that I had recently installed the MobilePress plugin.

Removing the plugin immediately resolved the issues and the temp files are no longer created.


No comments

  1. rbrambley says:

    I think you’ve now convinced me to disable mobile press too. I’ve had a few readers tell me they are getting mobile pages when in Firefox. That is frustrating, but this issue makes me worry.

  2. Tyler Reed says:

    Hey Jason,

    Thanks for finding the bug. We’re looking into a fix and will release it as soon as possible.

    @rbrambley are you using any caching plugins with WordPress?

  3. jason says:

    Tyler, thank you for stopping by. I’m glad you found this, and so soon. A few of my readers commented on how useful the MobilePress plugin is so it would be nice to be able to keep it.

    I was going to write an addendum to this blog entry clarifying that I’m not a PHP guru and (part of) the problem may be with PHP, but nonetheless, the issue doesn’t surface unless the MobilePress plugin is enabled and so that’s what had to go right away to get some relief from the IIS services locking up forcing a reboot.

    I looked on the author’s home page for an area where I might be able to drop them a line (is that you?) but could not find any, so I did the next best thing which was to post about it here and over at the WordPress site in hopes someone would find me – and it worked.

    Thanks again!

  4. rbrambley says:


    Yes. I use the WP-Cache plugin

  5. Tyler Reed says:

    Hi Jason,

    Just a quick question, in your php.ini – are the following config options set:
    * session.gc-maxlifetime
    * session.cache-expire

    @rbrambley Unfortunately cache plugins don’t play nice with MobilePress, often content is cached for the wrong device. We’ve tried several fixes, however none of them are ones I would want to release. We will keep working at it though.

  6. jason says:

    @Tyler Reed:
    php.ini is as follows:
    session.gc_maxlifetime = 1440
    session.cache_expire = 180
    These are settings that are probably default out fo the box because I don’t recall tweaking these.

    Thank you,