The error also intersects with DRM debates. Some players encounter it when attempting to run a purchased game without Steam (e.g., via a cracked executable). However, legitimate users suffer too – due to overzealous antivirus or Steam client updates. This erodes trust, as paying customers feel punished by anti-piracy measures. Valve has attempted to mitigate this by allowing developers to use a “Steamworks stub” that fails gracefully, but not all adopt it.
Corrupt API files are the #1 culprit.