Windows 3.1 build 101

Windows 3.1 build 101 is the official Release Candidate 1 build of Windows 3.1. It was mentioned in an internal Microsoft document from February 1992 and is also often referred to as RC1 in other documents. Disks 2, 6, bug report, and app tests were found on eBay in September 2018 and were bought by user AirportsFan. Files from these disks confirm that build 101 is indeed the first release candidate of Windows 3.1. Using files from the RTM build, this build can be installed.

According to the internal document, several third-party applications were tested on this build. It was released to testers on 14 February 1992.

File version
The file  from the RTM build of Windows for Workgroups 3.11 contains the version number , which hinted that RC1 of Windows 3.1 was build 101 before this was confirmed by the partial leak.