This specific build number (22621.1245) corresponds to an released in early 2023. It included several critical stability fixes, such as:

: Many X-Lite versions bypass standard Windows 11 hardware checks, such as TPM 2.0 and Secure Boot, allowing installation on unsupported, older PCs.

is a specific iteration of Microsoft's operating system , and the X-Lite version is a third-party, custom-modified build designed for extreme performance and low resource consumption.

: Core Microsoft apps, telemetry, and tracking services are stripped out to reduce background processes and CPU usage.

Addressing resource deadlocks in COM+ applications that could cause system freezes. Community Perspectives

Resolving issues where apps like or Adobe Reader stopped responding due to Exploit Protection.

“I don't usually recommend for people to use custom Windows OS. They break pretty fast and cause lots of issues down the road especially after a Windows update... don't forget about the huge security risk.” Reddit · r/Windows11 · 1 year ago Usage Considerations