Deli meat and cheese should be left out of the refrigerator for no more than 2 hours. If it is very warm - as at a summer picnic - then 1 hour is the maximum.
First of all, if you don't know how long it has been out, don't eat it.
Dairy products spoil easily and need to be refrigerated or eaten as soon as possible.
Probably no longer than 30 minutes...