Something went wrong. The "Save Site as template" action is not supported on this site
Reason for the Error:
When you try to save a publishing site as site template then you get the following error message
The “Save site as template” action is not supported on this site.
Even you deactivate the publishing feature, you still face the error.
Resolution:Below PowerShell will update the Single property page value in the SP Web object.
$web = Get-SPWeb http://Sharepoint.com/Publishing
$web.AllProperties[“SaveSiteAsTemplateEnabled”] = “true”
It can also be done via SharePoint desginer but i always like PowerShell
Happy Sharepointing :)