Cannot connect to SQL SERVER 2000

Hi,

I have some problem with my SQL SERVER 2000. Sometimes (I say sometimes because it's happen randomly) I am not able to connect to the sql server. The error occurs when I try to connect with entreprise manager, query analyser or ODBC (web pages).

Here the error I obtain:

Microsoft OLE DB Provider for ODBC Drivers error '80004005'

[Microsoft][ODBC SQL Server Driver][Shared Memory]SQL Server does not exist or access denied.

/admin/nouvelle.asp, line 39

I appliy all the patch I found on Sql Server 2000.
It's running on an Windows 2000 (I apply patch too...).

Can you help me .... I don't know what to do.

Thanks!COULD BE THE CONFIGURATION OF THE ODBC OF SQL SERVER CONNECTIVITY IS NOT CORRECT. OR MAYBE THE CONNECTION YOUR ARE TRYING TO USE IS NOT TRUSTED ONE (AUTHENTICATED).
TRY ONCE AGAIN SINCE YOU'RE USING WIN2000 TO CHECK YOUR OWN SYSTEM DSN IN THE DATA SOURCE (ODBC) - ADMINISTRATIVE TOOLS.