Hello
I have the following problem:
I'd like to check whether entered user, domain, password are correct for
domain user. Second need is to check local user credentials. What .NET
functions should I use?

You might have a look at a class I did a while ago for this.
http://spaces.msn.com/members/staceyw/Blog/cns!1pnsZpX0fPvDxLKC6rAAhLsQ!283.entry

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and another fact:
I use Windows 2000 workstation

William,

Thank You for the tip, this is what I wanted, unfortunately I cannot run
LogonUser function from advapi32.dll.
Maybe the following facts contain the reasons:
- this application is an asp.net application
- ASPNET and IUSR are Administrators
- my computer was changed a computername
- I am a domain user with administrator privilidges on this computer

Jacek

See this link under the Remarks for rights the calling account needs.
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/secauthn/security/logonuser.asp

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So according to the following text from article that You advised to get
familiar with ("The user account must have Log On Locally permission on the
local computer. This permission is granted to all users on workstations and
servers but only to administrators on domain controllers.")
means that if I work on computer LAP1 in domain DOMAIN1 as user USER1 who is
in ADMINISTRATORS group
and I want to authenticate USER2 from the same domain or LOCALUSER1(as local
account), they need to have some special privilidges? How to set them?

What about running asp.net application when nobody is logged on the computer?

My goal in details:
The only think I need to know is: whether DOMAIN1\USER1+his Password are
valid, (or LOCALUSER1+his password) then I need to check if USER1 is added to
local ADMINISTRATORS. Both these checkings should work when computer is not
connected to the network, so we assume that in case of LOCALUSER1 there's no
problem, but USER1 must be logged to this computer at leats once to leave his
credentials locally.

thanks

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