Applies to: ZWCAD 2018; ZWCAD 2017; ZWCAD Classic; ZWCAD 2015; ZWCAD 2014; ZWCAD 2012; ZWCAD 2012(ITC)
1) The most possible cause is that the customer is using remote way to use ZWCAD. Please tell the customer to use it locally instead of remote way. You can view the log error code by -103. For example, ZWCAD stand-alone license does not allow to be run by user who logs on with remote desktop.
2) Install and Run ZWCAD as an administrator;
3) Ensure your computer's system time matches the current time.