Symptoms
JSP scripts do not work after Plesk upgrade:
Page not found error displayed instead of a correct page.
Cause
Most likely Java application was deployed on domain not through Plesk Control Panel, so MIME types were lost in website settings during Plesk upgrade.
Resolution
Corresponding MIME type should be configured in IIS manually. Go to IIS manager, Web Sites, domain.tld, Properties, HTTP header, MIME types, New
Extension: .jsp
MIME type: text/html