Hi @gsicard, first two options:

1. As a test, set a different skin and try to load any post in the front-office again.
2. Turn on debug mode and review the output looking for a "weird" error/warning message. Share it here so we help you checking it.

Do you use any third-party plugin on your site?

Thank you.. I switched skin from Ark to Mystique and am able to read my posts. Ark and Business skins have the issues.

Debug brute force method gave this error just below where my content should be.
"Notice: Undefined variable: debug_jslog in /home/pathtomysite/htsrv/anon_async.php on line 46"

I will unistall the Ark skin and try again.
Thank you very much

@gsicard it would be interesting to find out where the problem is. Your site seems to work with a third-party (not frequently updated) skin, but not with the most updated ones.

Do you use any third-party plugin?

Something weird with the notice you're getting. There should be a $debug_jslog variable at config/_advanced.php. Have you touched that file to include your own customisations?

Indeed, please check if your config/_advanced.php is up to date and includes all the variables it should have.