I have spent TWO(2) DAYS on this stupid error:

An exception of type System.Security.Principal.IdentityNotMappedException was thrown.  Additional exception information: Some or all identity references could not be translated.

when reinstalling Microsoft Office SharePoint Server 2007 (MOSS 2007). Well, scouring to the ends of Google-land, I didn't find a solution. From what I found never included #3 step below. I finally figured that problem out myself. For all with this error:

1. Delete/Remove all SharePoint databases.

2. Go into IIS and delete the "SharePoint Central Administration V3" site (if it didn't get removed during an uninstall).

3. MOST IMPORTANT!!! - Go into IIS and under "Application Pools" and delete "SharePoint Central Administration V3" (or be like me who wasted 2 freakin days).

If you don't follow #3, your install will fail every damn time in every scenario (Basic, Advanced - Complete, Web, Stand-Alone) and these installs/reinstalls can take a very LONG time.