Just make sure that the new service user is in the QlikView Administrators group and that it has access to all the server folders. If you are using Active Directory in the Directory Services, make sure that the new user has access to the diretory or else you will need to specify a different user/password in the DS config.
Then, just update it in the standard Windows services dialog.
Hi Helen and Community,
When I ran into a similar problem, I applied Stephen's good advice above and then took it one step further: I made sure that the new service user account is a member of the machine's local "Administrators" group (not to be confused with the 'QlikView Administrators" group, where it must also be a member).
When I originally installed QlikView Server/Publisher, because an appropriate Service account had not yet been created by the Network Admin folks, I provided my own personal account credentials. My personal account was already a member of the machine's local "Administrators" group. Everything ran well.
Then as the Service account became available, after adding it to the "QlikView Administrators" group I then attempted to simply apply it to each of the QlikView services in the standard Windows services dialog. As a result, not all of those services would successfully restart. The problematic three were QlikViewDistributionService (Publisher), QlikviewServer, and QlikviewWebserver.
Following Stephen's tip, I modified the security settings for the "Program Files\QlikView" and "ProgramData\QlikTech" folder by granting Full Control to the new Service account. This permitted QlikviewServer to start, but not QlikviewWebserver nor QlikViewDistributionService. I am not familiar enough with the folders used by these services to hunt them down, so instead (after backing out the folder privileges mentioned above) I took the easy route:
I added to the machine's local "Administrators" group the new Service account and, after a server reboot, now all 5 QlikView services function without any problem. (Hard-core security people may frown on this shotgun approach, rather than applying pin-point privileges? An alternative might be to uninstall the QlikView server and then reinstall and supply the new Service account credentials...)
I hope this helps.