
This fix is a special one that this home for me, and this usually happens a lot to me. For some strange reason I would always get a dreaded Error 500 whenever I installed to many wordpress plug-in or tried activating certain ones. I did some research and found a two really quick fixes that should work.
First 500 Error fix
Firstly create a new file in notepad or similar and enter the following:
php_flag register_globals off
register_globals = 0
memory_limit = 64M
Save this file as php.ini and upload it to your /wp-admin/ directory of wordpress. This will usually take care of the problem. If this doesn’t work try the second fix.
Second 500 Error Fix
Create a new text file in notepad and add these lines to it:
AddType x-mapp-php5 .php
AddHandler x-mapp-php5 .php
Then upload it to your root directory, where wordpress is isntalled, and rename it .htaccess. If you already have one of these files DO NOT overwrite it just edit it and add the two lines above.

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