Quote Originally Posted by NoHug4u View Post
After installing XAMPP I set up my local domain by editing c:\windows\system32\drivers\etc\hosts by adding the line: 127.0.0.1 www.mydomain.com. After doing some searching on the internet, my understanding is that my local host is now www.mydomain.com and that I should be able to run fix_cache_key by entering the url www.mydomain.com/store/fix_cache_key.php. That makes sense to me, because before I encountered my problem I was able to access my admin page by entering the url www.mydomain.com/store/myadmin/

If this is incorrect I'm not sure why. Just to test it, I did try to access fix_cache_key by substituting localhost for www.mydomain.com. Still no luck...
I agree with the theory of Torvista, after all why would the address start www. as you are using localhost not the world wide web.