internal server error on cell phones

Hi-

I transferred my files up to a test domain (just the landing page) along with all of the other files and folders you said in instruction page. Web site is working perfectly on PC's and tablets. On cell phones I am getting "internal server error". If I go onto a mobile web site tester page it works... but not on actual cell phones. I have tried 6 different cell phones. All the same - " Internal server error".

I called my host server and they said all settings on their end appear correct. They are pretty sure the issue is somewhere in the code.

Please let me know where I should look or how to correct.

Ivan

as an update on this- turns out by turning off my .htaccess file in the root directory on server the problem was solved. I renamed the file as a test and mobile started working. So something in .htaccess was causing the problem. I have alerted my hosting service to correct the file and reinstall any necessary code.