If you have purchased a USB licence trough airmail, then you have received a number of licence (a 11 characters string)
and physically a memory stick already registered with this licence (a password stored in the file '.GiDauthority' on the root of the memory stick)
By your message seems that do you have the memory stick but the related '.GiDauthority' file is missing, it is not?
Note: Maybe the file exists but you can’t see it because has the hidden attribute.
In any case don’t worry this file could be recreated knowing your GiD USB licence
To do it:
1- Install GiD in your machine (the installer could be downloaded from our web www.gidhome.com
), probably do you already have GiD installed.
2- plug the memory stick, start GiD and go to its menu Help->Register GiD…, and select in the list that appear the ‘usb one’ (not the ‘Local machine’)
3- and then its identifiers will be showed in the ‘Enter password window’ (name, sysinfo, version)
4- go to the webpage suggested: https://www.gidhome.com/purchase/passwords
, select your options (GiD version, type=Usb, Permanent) and use your licence number, and the name, sysinfo (it is recommended to use copy/paste to avoid human errors), and the webpage will return the password for your memory stick.
5- Enter the password in the ‘Enter password window’ and it will be saved in the related '.GiDauthority' file (and also locally in the scripts/TemporalVariables of GiD)
Then you can use your memory stick in the machine you want.
Be careful to not delete this file of the memory stick or you must repeat this process.
Off course your USB licence must match the main version of GiD (e.g. if do you have a USB licence of GiD 13 you can use it for all GiD 13.x versions, but not for a GiD 12.x version)