Q: For this release, can I use regional settings other than English (United States)?

A: No. As noted in the Visual Studio 2005 Team System Readme:

2.1.4 English Only

Visual Studio 2005 Beta 1 Refresh with Visual Studio 2005 Team System has only been tested on English versions of the operating system, prerequisites (including Microsoft Office System) and with US Regional settings. Future releases of Visual Studio 2005 Team System will support other languages and locales.

In Control Panel, open Regional and Language Options. On the Regional Options tab, select English (United States) and then click OK.

Applicability: Visual Studio 2005 Beta 1 Refresh with Visual Studio 2005 Team System