Error when trying to access my website

[redbud]

When I try to access my website I get the following:
Fatal error: Incompatible file format: The encoded file has format major ID 1, whereas the Loader expects 4 in /home/jk0126/public_html/index.php on line 0
What does this mean?
It appears you have upgraded from Website Builder to RVSite Builder. Is this causing the problem? Do I have to rebuild my website?

[essellar]

It's not what's causing the problem -- the change from SiteReptile to RVSiteBuilder was because of the problem. SiteReptile created sites encoded for Zend Optimizer/Zend Guard, and the version it used is incompatible with the current version of Zend Optimizer. Zend is aware of the problem -- version 5.3 is not compatible with previous versions -- and has no plans to fix the problem.

The problem would have surfaced when the servers were upgraded, and that was quite a while ago now.

And yes, you will need to rebuild the site, unfortunately.