HTTP/1.1 500 Internal Server Error with GZip

Hi,

I have just upgraded my site to using WordPress and am having trouble with caching and GZip. I noticed the googlebot was returning 500 internal errors. I uninstalled the caching plugin and just tried a GZip plugin and am getting the same results. If I deactivate the plugin the errors do not occur.

I have been using http://web-sniffer.net/ to try and track down the problem but I am stuck now and do not know how to proceed.

Any help would be appreciated in how to go about trouble shooting this issue.

http://www.thirsk-homeitsolutions.co.uk

Regards

Michael