Updated - Hang on; is this server an API Gateway instance? If yes, then you must perform user management only via API Gateway UI since both API GW and IS use the Administrator user. If you change it on the IS in the back, the passwords are reverted.
If not, then take a look at the following -
NP and I can both assure you that this is not the case, irrespective on wM version; user management changes are permanent for an IS license.
* You can increase the logging level, as NP has asked above, and collect the relevant logs
* If you use Central User Management, then investigate from that point as well - perhaps a permissions issue in the DB
* Check the directory and file permissions of the /…/IntegrationServer/instances/yourInstanceName/config folder and its subfolders
I recommend that you create a support ticket, as this is unusual.
KM
#webMethods#Integration-Server-and-ESB#Integration-Server