how to get "out of box" state

[samo50g]

Thanks for your replies. Manuals etc. only say about "soft" reset. I am not an expert for calculators and other computer stuff, so it is better not to talk too much . I installed this third party software:

http://www.software49g.gmxhome.de/index.html

It made a chaos in my calculator, for instance after using CLEAR function the display became almost black, etc. So i do not want to hear any more about anything which is not a part of out of the box state.

I think I managed problem. so I downloaded and installed ROM 2.15 according to instructions in zip file:

https://www.hpcalc.org/details/7097

To the best of my knowledge the old and I guess corrupted (infected with third party software) ROM (same version, so 2.15) was replaced by the fresh installation of ROM. I also purged content of :0: in Library "directory" and I removed all third party libraries from :2: Library "directory".

it seems all is fine now, I would like to hear your comment if I must do anything else and if my explanation holds water or I made some (terminological) mistakes. thanks.