Hi, I’m a new user.
After first backup I went to destination folder and found three .zip files with .dlist, .dblock, .dindex suffixes.
The biggere among them, .dblock, contains many files with no extension.
Where can I find backup files?
Duplicati is designed to split files into small blocks which are identified by their hash. That is what you see in the zip file. This allows to remove duplicated files or partially modified files. Because of this, the result is not readable directly, only by Duplicati or another special tool. The files can be restored in the Web UI or Command line.
If you are interested how it works in more detail: