Hi,
first of all I want to thank you all for your patience and help. I know that patience is needed to help people from all over the world via internet.
Sorry for my late reply here.
I would like to ask a few more questions.
I gave my phone now to a second phone shop and now it works. My Samsung is recognized by Windows, it charges. I will ask the shop again if they replaced the USB connector. I forgot.
But as a paranoid I have some mor questions, I am sorry for that in front of you normal people ;-)
- When I took my phone back (
from the first phone shop) the date was set to january 1st. Why that? How can that be? It was charged full there because I could not charge at home. Did they remove the battery and set it back? 
- Could the error (that I described in my first post, no recognition of  the phone in Windows etc) have been eliminated when I did a 
hard reset of the phone?
	
		
	
	
		
		
			I dont believe  they could get into your phone , because  they would have to allow access  prompts to connect  to their  computer and to do that you need to get into the phone to allow it .
I'm not sure how the date changed possible  without  the sim in it . No repair  shop will work on a phone  without  you factory reset or you unlocking  it and watching them look at the issue  in front of you .
		
		
	 
	
		
	
	
		
		
			1.  The shop could have gotten into your phone without your password.
		
		
	 
I do not want to know how, I just want to know 
if possible and 
how the chance/probability is, for each scenario.
1.) Is 
access to my phone without the knowledge of my passwords possible or not?
2.) Is it possible that they 
found out or cracked my codes for gaining access?
3.) After a bit of investigation I found out that there is software to rescue data both from ios and android systems (For example: Dr. Fone). Maybe with software like that?
4.) Let's assume, my usb connector for data transfer was 
damaged. Could the shop have gained any access to my phone, e.g. via wireless connection (WiFi,...)? Does Dr. Fone or an Alternative work without usb cable connection?
5.) Is there any other way I forgot?
I am really sorry for that kind of questions, 
really, by heart. 
Your reply is appreciated.
ease00