If a visa application has been denied by one Schengen consulate already, the passport will have been endorsed on the observations page with a stamp in ultraviolet ink that gives the date of the rejection and the post rejecting it. This may or may not be visible to the naked eye but will be visible under a UV light.

Due to the lack of an effective centralized Schengen visa database as okko noted, any other Schengen consulate to which an application is submitted will always check for that stamp to determine whether a previous denial exists. If so, they will contact the consulate that placed the stamp to determine the details of the case.

Local post policies largely determine the acceptance or rejection rates for each country and the paperwork required to receive one. However, some general observations dealing with consulates from Schengen states in multiple countries are that France, Spain and the Netherlands are the easiest to satisfy for C-class visas while Germany and Italy can be very sticky. That said, there are exceptions to every rule and local posts may vary widely.