How to fix the error: Failed to update the system registry?

Symptoms

When starting up BricsCAD, a message box appears:

Failed to update the system registry. Please try using REGEDIT.

Cause

Running BricsCAD requires access rights of at least the Main user group because of registration of an OLE Server class in HKEY_CLASSES_ROOT.

Solution

Log in as main user (or administrator) or choose Run as administrator.

Important note about Windows 8.1 and higher:

It is not sufficient to log in as administrator or main user, you also have to start BricsCAD by right-clicking the shortcut and choosing Run as administrator.