When qbdataserviceuser26 is not working the services would be then transferred to the Applications where it does not work  in the local computer where it stops working and then starts. In qbdataserviceuser26 what happens is the services in data base server manager stops.
If you create a new user window for account purpose if any different database manager in logs of the data to the window system and the computer it allows to provide the windows services to log. In many situations the software is downloaded from the ASP.NET user account the the services run with the database store.
qbdataserviceuser26 kind of issues are generated in QuickBooks for the server manager and services which there are  QuickBooks data service user which it no longer needs for the program in the simple of the ays to left over folders for the services which are being used currently.
If the account holders have administrative privileges then the account might not get effected by qbdataserviceuser26.
When the qbdataserviceuser26 service error occurs the data base managers saves all the running data so that they will not suffer from data loss and the security reasons too.In qbdataserviceuser26 the services that are stopped in database server needs to reinstalled or a restart of quickbooks can be tried also.

Further Reading