For NoMachine users v. 7 or later
Starting from NoMachine v. 7.7.4, support for USB forwarding on Windows XP has been dropped since the new version ships updated drivers which are no longer compatible with XP systems.

New installations will therefore not install USB drivers, while upgrading the current version will uninstall the older drivers which were affected by an issue leading to a possible privileges escalation on Windows: https://kb.nomachine.com/TR10S10388

This above applies to both client and server side.

All the other services (printers, disk sharing, file transfer etc ...) continue to work regularly.

Ref. announce of release v. 7.7.4:
https://kb.nomachine.com/SU10S00227
 

For NoMachine users v.6
As well as v. 7.7.4, NoMachine version 6.16.1 drops support for USB forwarding.

Ref. announce of release v. 6.16.1:
https://kb.nomachine.com/SU10S00228