QuickBooks POS Error 121 occurs when you sign in with other than the 'System admin. QuickBooks Error 121 says- 'you do not have permission to choose the time-outs. QuickBooks point of Sale is a superb application to power and manage your business curve. QuickBooks POS Error 121 happens when you sign in with other than the 'system admin.' QuickBooks errors 121 says Quickbook pos 121. QuickBooks error, feel free to contact the team who is here to assist you 24/7 hours. You can easily get in touch with the expert team by dialing the QuickBooks customer support phone number 1-800-993-4190.