You can restart the UWL service without restarting the portal.
Procedure
In the SAP NetWeaver Administrator choose OperationsSystemsStart&Stop.
Select the Java Applications tab.
Select com.sap.netweaver.bc.uwl application within the
results.
Choose Restart.
As a result, the following message appears: "Application is restarting
asynchronously. You can see the current state by choosing the
"Refresh" button in the status table".