Can't get pro key to work on two of my devices... in Sync Troubleshooting Posted September 17, 2017 · Report reply Figured it out. Had an old version of Sync running. As mentioned, had it running for a long time and since it worked perfectly, I never upgraded it. Installed the latest version and it took the license file easy-peasy. Also, followed the instructions to upgrade the app on my Netgear NAS and it all went well except for one step. The instructions said to unlink my NAS using the gear icon in the Sync app (launched via the NAS app tab). This did not work. So I just shut off the app directly on my NAS, clicked the Remove link on the NAS app tab and all went well from there. Once the NAS was upgraded I followed their directions and the new NAS app took the license perfectly. So make sure you're on the latest version on each device that's giving you trouble.