We have received several reports of problems accessing MathSciNet. The library has reported the problem, and we are working on resolving the issue, but we do not have an estimate of when access will be restored. In the meantime, library users may want to search Zentralblatt MATH as an alternative.
Update (4/14): As of this morning, access has been restored. Please contact Brian Quigley if you continue to have access problems.