Has the application section access? Because maybe is not a problem with the license and the problem is that the user is not included in the section access.
If this is not the case, check in the QMC that you have the option of Allow License lease enabled. Also if you have the disabled the option Allow dynamic CAL assignment, the user must be included with the correct domain.
The 'access denied' error message is typically associated with Section Access. If the same user can open other QVW files not created by them, then Section Access is likely the issue. The user needs to be defined in the Section Access statement/table. See this video for further info on Section Access: https://www.youtube.com/watch?v=Cq4QzR9s7AA
Hope this helps,