Received an error “Failure decompressing data from a cabinet file” when trying to save a site as a template. This is a known issue with no solution – occurs when we save a site as a template with a lot of content.
If you receive this error after increasing the list/site template maximum size, Make sure its below 500 MB. (By default, the maximum size of the list or site template is set to 10 MB!), Typically 50 MB should be ideal.
stsadm -o setproperty -propertyname max-template-document-size -propertyvalue 50000000
There is a hard limit of List/Site template size of 500 MB. So set the value less than 524288000, or you will get an error when saving the list as a template!
As per the above KB, You may receive an error even your site template size is lesser than the configured value! So what other options left to us? Export/Import! In another case, I open the site in SharePoint Designer, and deleted unused document templates from _cts folder, tried saving it again, it worked!