Troubleshooting a Fatal Error on WordPress Update

When I initially applied the WordPress 2.8.6 update, it failed and returned the following error message:

Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to
allocate 2355240 bytes) in directory_path/public_html/wp-includes/http.php
on line 1331

After some unsuccessful troubleshooting, I realized that the only significant changes I had made to WordPress since I had applied the prior update was I had added a number of new plugins.  I thought that might the source of the problem, so I went through the most recently installed plugins and deactivated them one-by-one.  After I deactivated each, I then attempted to re-run the 2.8.6 upgrade.

Eventually the upgrade script worked.   I had to deactivate four plugins however before it was successful. Then, after the upgrade was applied, I reactivated those four plugins and everything was back to normal.

I am not enough of a WordPress guru to know if the problem was related to the total memory used by all four of the plugins, or if it was just an issue with the final plugin that I deactivated (I can test that next time I suppose…), however if you are seeing a similar error message, hopefully this will work for you as well.