IsLoginValid(Microsoft.SharePoint.Administration.SPGlobalAdmin, String, Boolean) Method
The IsLoginValid method of the SPUtility class uses the specified global administration object to determine whether the specified user name is valid and whether it corresponds to a user account.
Parameters
globalAdmin A Microsoft.SharePoint.Administration.SPGlobalAdmin object that represents global administrative settings for the server or server farm.
strLoginName A string that contains the user name.
bIsUserAccount true to specify that the account is a user account; otherwise, false.
Return Value
true if the user name is valid; otherwise, false.
Requirements
Platforms: Microsoft Windows Server 2003
Security: Code Access Security