Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 24 bytes) in /public_html/community/engine/lib/database.php on line 271

I tried upgrading form 1.7.1 to 1.7.3 the other day, but that broke my profile pics, so I removed that and uploaded my saved 1.7.1 files.  So, today, I'm getting this Fatal Error message.  I've gone so far as to remove all the installation files and upload the new 1.7.3.  The only file I uploaded with the 1.7.3 files was engine/settings.php.  I'm still getting the Fatal Error.

Can anyone help?