A: See the following Community Solutions Content:
Author: Prashant Lad, Madhusudhanan Padmanabhan MVP
While installing Visual Studio 2005 Team Foundation Server you get an error that says, “The installer has encountered an unexpected error installing this package. This may indicate a problem with this package. The error code is 26403.”
The error comes up while adding the TFSIdentity user to IIS_WPG group on the application as the machine is unable to contact the domain controller to get the user.
To resolve the issue, you need to add an entry in the hosts file pointing the IP address of the domain controller against the domain address.
To add an entry in the hosts file
- In the Run dialog, type “notepad c:\windows\system32\drivers\etc\hosts”, this will open the hosts file in notepad.
- At the end of the file add an entry like “192.168.0.1 domainname”
- Save & close the file.
- Restart the machine
Before you run the installer again, make sure to do the following:
- Delete all the files in %TEMP% folder on the application server.
- Delete the databases created by the installer on the database server. The rollback process doesn’t delete the created databases.
- Make sure that TFSIdentity user is created on the domain controller and not on the application server.
Applicability: Visual Studio 2005 Beta 1 Refresh with Visual Studio 2005 Team System