I encountered across an unusual issue today when I migrated a Wordpress website from a hosted site to localhost. My Home page and Admin section were working perfectly fine, but whenever I visited any category pages or single post pages, it gave me the following error. 
Page isn’t working. Currently unable to handle this request. HTTP ERROR 500
This was bizarre, and after a lot of searching I found this solution Try flushing your mod_rewrite rules: Dashboard -> Settings -> Permalinks Save settings (no need to make any changes) That's it, Boom! I hope it helps someone facing a similar issue.