First off.. please make sure you post your questions to the proper forum for your model terminal - your question will receive an answer much more quickly. :)
These machines aren't like a laptop where you can reload the OS onto them if they get messed up. The base software is loaded on ROM internally, so you can always wipe the terminal and start from scratch. Companies (like yours) can then build application specific files to load into them.
Here is the standard way of accessing the programming-level menu which will allow you to wipe the memory and enter the proper download parameters for the file you want to load.
- Press the F2 and F4 keys at the same time.
- You will see a prompt for "system password"
- Press: 1,alpha, alpha, 6, 6, 8, 3, 1, Enter
This will bring you to the system menu. From here you can scroll down to System Menu Screen #2 where you can Clear RAM and flash the RAM files. From there your company can treat the terminal as a blank slate ready to program.