Unfortunately, re-installing the latest version of NI-VISA didn't work for me.
I am running in a Windows XP box, to control three old HP6654 power supplies. They are GPIB0::0::INSTR, GPIB0::1::INSTR, and GPIB0::2::INSTR. The first device to initialize is GPIB0::2::INSTR.
MAX is talking to the device, but I don't know if it is using VISA or not. We are able to Query "*ISDN?".
NI Spy (NI IO Trace) shows viOpenDefaultRM() runs fine (returns 0), but as soon as viOpen( 0x02A08970, "GPIB0::2::INSTR", 0,0, 0x0000000), it returns a status of 0xBFFF009E = "A code library required by VISA could not be located or loaded"
I've tried recompiling the CVI 8.5 source with CVI 9.0.1 thinking DLL issues, but I got the same error (0xBFFF009E).
Note: this machine used to work with these supplies, back in March 2012. Then a user installed the drivers for a USB-to-GPIB (by ICS) back around April timeframe, and my application's logs indicate that it stopped working from that point on. He's uninstalled the driver (and re-installed it back, then I uninstalled it), since the device is no longer on that computer, but we believe it corrupted the VISA environment, but cannot be recovered.
- I've tried to install the latest versions of NI-GPIB and NI-VISA, and Device Drivers 2007, but got the same error (0xBFFF009E).
I'm trying to download (Device Drivers 2012 Aug) now to see if this works, but I don't think it will.