Someone told me that you can use a chess database for correspondence chess, but this seems a little like cheating. Does anyone has some information on this subject.
According to the official rules of the International Correspondence Chess Federation, you are allowed and encouraged to. It is regarded as learning an opening. Of course, there are different rules for some sites, but most sites follow the ICCF rules.
My teacher always said that using engines and suchlike didn't matter, as generally players in correspondence chess can analyse deeper than a computer can. That was a few years ago, so the state of technology might have changed now. Also, this probably only applies if you are above certain level of ability.