Well, I'm here once again... I've managed to install pgsql 7.02 on my NT box NT 4.0, SP6) with the latest cygwin's release (1.1) and I am using cypipc 1.05... I keep getting "error semaphore semaphore not equal 0" each time I make a query, and sometimes the backend freezes... Joost was right, it seems to be cygipc fault, the above error message is raised from sem.c in cygipc sources... Is there anyone who knows how to solve this problem? Andrea