If you get the error 'License file does not support this version.' you probably installed a new version of Mathcad Prime but are using a historic old license file.
So if Prime starts up with padlocks:
you're in 'Express Mode' and there's a problem with the license.
If you have a look in the M' menu > Options > License:
You will see that your license is 'Invalid':
If you're using a locked license
If you're using a locked license you can see the used license file in the File section. Please attach that file to a support case to us and we can generate a new file for you.
If you're using a floating license
If you're using a floating license you can see the server name or IP address in the Server field. Then you probably need to contact the administrator of that server and ask that person to reach out to us for an updated license file.