This build is referenced multiple times in 5048’s Setup Loader for Migration (upgloader.dll) as a minimum requirement to complete an upgrade from one CBB (component based build) to another. This was first reported by BetaArchive user DjDeedahx1)BetaArchive – Interesting find in Longhorn 5048 setup, DJ Deedahx. The exact branch of this build is unknown, but is assumed to be winmain. A file called preupgradenotice.txt in 5048’s installation disc also references this build. The file reads:
Longhorn ReadMe File for Internal Upgrades
** Restricted upgrade scenarios **
Upgrade is *NOT* supported in the following scenarios for this RI:
1. OS being upgraded is a build lower than 5019 *
2. OS being upgraded is an INF build (only CBB -> CBB upgrades are supported) *
3. OS being upgraded is newer than the one being installed
4. OS being upgraded is 64-bit, setup being run is x86
5. OS being upgraded is a server build
6. OS being upgraded is LH Home, setup being run is LH Pro
7. OS being upgraded has multiple OS’s installed on the target partition
* Upgrade support is planned for these scenarios in future milestones.
Download the complete text file here.
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