Server Configuration > Service Packs and HotFixes > Rolling Back HotFixes
  
Rolling Back HotFixes
Rolling back a HotFix removes the updated class files installed with the HotFix. HotFixes that are rolled back on the Windchill RV&S server are not mandatory to roll back on the Windchill RV&S client. Clients are still able to connect to the Windchill RV&S server with a rolled back HotFix; however, the server.log file records a warning to indicate that the HotFix is installed on the client, but not on the Windchill RV&S server.
If a service pack was installed and it included the removal of previously-released HotFixes, rolling back that service pack effectively restores those HotFixes on the server and client.
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The rollback process is only supported for HotFixes that are installed on the Windchill RV&S server and distributed to clients using the patch distribution utility. The rollback process does not apply for custom or untested HotFixes that have been installed individually.
The rollback option works only for the most recently installed update. You cannot roll back combinations of HotFixes, service packs, or multiple HotFixes.
In a multi-server environment, all servers should be maintained at the same HotFix level. If a proxy is hosting projects locally in a multi-server environment, it is also important to maintain that proxy at the same HotFix level. If a server-side and client-side HotFix has been installed on multiple servers and is then rolled back on one server, it is advisable to roll the HotFix back on all servers. Failing to rollback the HotFix on all servers will create a situation where one server requires the client to roll back the HotFix, and another server requires the client to install the HotFix.
When rolling back, a dialog displays the HotFix or service pack that is being rolled back. For service pack rollbacks, you are also prompted regarding a database rollback if there were schema changes associated with the upgrade.
Rolling Back Server-side HotFixes
Rolling Back Client-side HotFix