Use /gun to rename a group.
To use the /gun command, you must be a member of the Team Foundation Administrators security group. For more information, see.
Specifies the group identity. For more information on valid identity specifiers, see.
Specifies the new name of the group.
Required. Specifies the name of the application tier server.
The following example renames the group "Coho Winery Education" to "Coho Winery Product Support."
>tfssecurity /gun "Coho Winery Education" "Coho Winery Product Support" /server:MyATServer