bloggingways

The first thing you should do when troubleshooting the WP internal server error is check for the corrupted .htaccess file properly. If you have configured something unexpected, then do the following to remove your doubt proudly and see whether it works or not

First of all Backup your current .htaccess file.
Now Delete all of the information from your .htaccess file and save it i.e. upload a blank .htaccess file.
Your blog should now be usable again so go into the admin area and set your permalink structure again.
Open your new working .htaccess file in an editor. Now copy over all the non WordPress .htaccess information from your old backed up .htaccess file ex. any search engine htaccess information, Security codes, IP blocks etc – basically everything Non-WordPress that you added before.

If you find that adding all the code from the previous .htaccess file is causing an Internal Server Error again then remove it all and enter the information back to the working .htaccess file line by line to see that what is causing the problem etc.