When Windows settings has end of daylight saving period set, but does not have beginning set, WinSCP fails.
Emails with Sascha Kästle in December 2009.
Many users report that changing timezone to another one a reseting the actual one, fixes the problem.
Fixed. When this occurs, WinSCP ignores daylight saving settings. This is actually not ideal, because apparently there is daylight saving in place in the respective timezone(s). But that's all what we can do about it.