If you are looking for a high-performance video player natively for PC, industry-standard alternatives often provide better stability and feature sets: Key Advantage All-around use
If your .vdx is actually a (rare), try:
KMPlayer has been around for two decades and is famous for playing broken or corrupted proprietary files. vdx player for pc
Leave the exact file size and source (e.g., "Came from a 2008 Samsung DVR") in the comments below for specific advice. If you are looking for a high-performance video