Please see this part of an email that I have found from another SQL forum. I think this may sort the problem out:
I learned that when changing your domain user password on the WinXP client, you will lose registered SQL
Servers in SQL Enterprise Manager. In addition, you applied the method in KB 323280 but the problem
persists if you change the password.
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Based on my experience, even after applying SP1 for Windows XP, we may still experience the same
problem. The methods in the following Knowledge Base (KB) articles should solve the problem you met
with:
323280 FIX: Registered remote servers disappear from SQL Enterprise Manager in
316994 Denied Access to Encrypted Files After You Change Your Password
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Nevertheless, the fix in XP service pack 1 only works if the registry key "MasterKeyLegacyNt4Domain" is
set on the Windows XP machine:
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography\Protect\Providers\df9d8cd0-1501-11d1-
8c7a-00c04fc297eb]
"MasterKeyLegacyNt4Domain"
Type: REG_DWORD
Value: 00000001
To add that key, you can follow the detailed steps below:
a) Open Registry Editor (Start-> Run -> Regedt32)
b) Go to the following key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography\Protect\Providers\df9d8cd0-1501-11d1-
8c7a-00c04fc297eb
c) Create the follow value (Edit->New->DWORD Value):
Value Name: MasterKeyLegacyNt4Domain
Value Type: REG_DWORD
Value: 00000001
d) Change your network account password and login again to see if the problem goes away.
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