After poking around, I found the old descriptions were still in a file called
I tried to delete this file and even so - the old description still show.
Since the OPC client PC initiated the read request the client is expecting a response and reads the data from the server but after the initial startup it is the OPC server which notifies the client of any change in data.
Keeping that in mind, if the OPC client machine is not configured to allow access from the OPC server then it will never allow any change in data notifications through and will never update the tag values.
when Im trying to update the Alarm Desc field for one or more alarms (these are advanced alarms), After saving, packing, compiling, and running the project the alarm descriptions appearing on the alarms screen are somehow the old descriptions, not the new ones.
Even when I turn the alarm off and turn it on again - the old description still appears.
You can modify DCOM security in the program found in the Win NT\System32 directory.