It has been very simple with Xcode.
a) export from current working machine
1. Open Organizer in Windows menu.
2. Click Devices, if you are not there.
3. Click team name under TEAMS section.
4. Click Export at the bottom bar, fill file name and password to protect this file.
b) import from new machine
1) Go to teams section as we have done.
2) Click import at bottom bar this time.
3) Choose file and input password protecting the file.