Siemens discontinued 802C for many years, no support any more. I attached OP and Prog. manual as you reference. I thought you may need initial clean the system , but you need have services and start up experiences, back up all system data , such as NC MD, and PLC program, which much more important than you "No NC Program" problem. 

if you are not sure, don't try to do it. I suggest you : if you can see NC memory still enough and you can make new NC program to run your products, just keep like that.   

AutoGen_b7ac4

Hi

I cannot open/select/remove any program files. When I go into "programs" menu I get a message "No program availible!" even when the actually selected program is availible on the list.

On the button menu only "new" and "memory info" are availible.

When I click new write some gcode manually I can execute the program, but after closing it it cannot be open/selected again.