If you see XML-related errors when loading vMix, your configuration files are likely damaged. The official fix is to:
If you encounter errors while trying to register version 26.0.0.45, try these standard fixes recommended by the vMix Knowledge Base : Lost Registration Key - vMix
If a valid license key stops responding or throws a registration error in build 26.0.0.45, execute the following diagnostic fixes to resolve the issue: Clear and Re-register Corrupt Licenses
These programs look like legitimate vMix files but open a backdoor to your computer.
Follow these steps to ensure a clean, error-free registration process:
Drainage Devon