The problem is somehow connected to personal firewall installed in the system. It’s a Kaspersky Internet Security 2010. It adds “Kaspersky Anti-Virus NDIS 6 Filter” service to every network connection, see attached SC1.jpg.
So we have found this workaround:
1. Plug AWUS036NH and install IS_AP_STA_RT2870_D-1.4.9.0_VA-2.3.9.0_W7-3.0.9.0_RU-3.1.4.0_.exe
2. Open properties of the newly installed wireless connection
3. Disable (uncheck) the Kaspersky Anti-Virus NDIS 6 Filter, see SC2.jpg
4. Reboot PC with plugged AWUS036NH
5. Open properties of the wireless connection and enable the Kaspersky Anti-Virus NDIS 6 Filter
6. Open Ralink Utility – it works!
We don’t know whether it’s an only Kaspersky related issue or the same problem exists with all personal firewalls like Symantec Internet Security, McAfee Firewall…