Windows 1.0/Premiere Edition

Windows 1.00 Premiere Edition is a preliminary release of the Windows 1 operating system developed by Microsoft.

It was released to the Euro-Asian Beta Group by betaguy224 and OBattler, and later to BetaArchive by Namronia. This build has been later proved to be fake, as the kernels of the leaked build, and Windows 1.01 were the same.

The Project Manager of Windows 1, Tandy Trower, stated: "But by the early summer of 1985, we were still not close to being done, so Steve declared we should release a preliminary release that I dubbed the Premiere Edition, which we provided to key application vendors, analysts, and members of the press for feedback and in partial fulfillment of Ballmer’s promise to ship the product that summer."

According to Trower, the memory management code of the operating system needed to be rewritten at a later point in development: "Then just at the point I was starting to feel more optimistic about wrapping things up the architect of the memory management code told me he found a critical defect in its design and would need to re-write it, basically rendering all testing to date useless. I pleaded with him to find an easier way, but after a thorough discussion there was no option other than to let him proceed and restart the testing process."

A screenshot once purported to be of the Premiere Edition was later proven to be fake, being only the result of a few modications made to files in the RTM version of the operating system.