I started the program after following instructions.
Now the program started with "synchronizing with network"
That means it has to download again the whole amount of GB's of data like the prog done it before?
That is correct. Because the "blocks" folder was missing, it needs to redownload the entire blockchain since that is stored in the "blocks" folder.
B.t.w. this time I got a question when starting Bitcoin Core, It asked if I wanted to store on Desktop or custom location, Application Support.
I have chosen Application Support.
Yes, that is good.
This program Bitcoin Core is not for faint-hearted...
Of coarse I keep backups!
Now see how long it will take to pull in the whole Block chain.
Should I keep all debug files, etc that are still on Desktop?
After removing Bitstamp, it's files stayed also on my desktop... I don't know which ones belong to Bitcoin Core and/or to Bitstamp?
No, you don't have to. All of the files I told you to copy earlier can be deleted from the desktop.
Thanks for the assistance so far.
I will inform when blockchain is in.