WHY would my checks (reports/ EVERYTING) start printing from last (page/ transaction/entry/ whatever) to first (page/ transaction/entry/ whatever)???

For some reason, this afternoon my payroll printed from Z-A instead of A-Z (although the register assigned check numbers from A to Z as usual.) What this is did of course is throw the entire batch of checks out of sequence.

I'd blame this on my accounting program (and spent most of the afternoon digging for a preference, option or command to change this, when it dawned on me that my reports were printing from last page to first too. I noticed that in other programs, that my reports were printing last page first, but I haven't printed enough things out to realize this is a system problem. (v. software) (Yes?? No??)

I can't for the life of me find what/ where/ how to correct this "order of printing"...
The correct printer is installed...
Supposedly the correct driver is installed
and to my knowledge, the right "checks" are selected/ same paper as always is being used.

Help????