Hi,
I want to try out new installation on the same computer. Can I use an 3CX Backup created in Debian and use it in a new installation on windows ? and also an backup created in Windows in a new installation with debian ?
Yes, it is possible but have in mind that you can not use a backup which was created in a higher version of the 3CX PBX and restore it in a lower version (eg create a backup in v.15 and restore it in v14).