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VS code will stop you from connecting because it can also be a sign of spoofing, that the remote computer is not the one you think it is. So good security if you assume your remote computer never changes, which is a bad assumption in our case.
If you have a saved entry for csil.cs.ucsb.edu or linux.engr.ucsb.edu for example you may need to delete and readd said entry.
"invalid credentials" means that you changed your password and your current credentials do not match your saved credentials.
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