Quick Books Problem

Not that familiar with QB, have client using it for 2 years, recently had problem with the payroll feature. Click on payroll and scroll to employee checks, screen pops up says to update, when you hit ok for update everythinbg freezes, nothing works. She contacted their support line and was told it was a Norton System Works conflict. Removed Norton still have same problem. Everything works except this one issue. It didn’t start until Dec. 31. Any assistance greatly appreciated.