Is the registry key "NI-VISA FOR WINDOWS 95/NT" a reliable way to detect if NI-VISA is installed?

[Jim West]

Is the registry key "HKEY_LOCAL_MACHINE\SOFTWARE\NATIONAL INSTRUMENTS\NI-VISA FOR WINDOWS 95/NT" still a reliable way to detect whether NI-VISA is installed on a computer?

There was a thread from 2002 in which this was referred to:

http://forums.ni.com/ni/board/message?board.id=170&message.id=37862&requireLogin=False

I didn't find anything more recent.

Jim

[Dennis_Knutson]

Hi Jim,

I haven't used the registry key but I think a sure fire way is to perform any VISA operation such as VISA Find Resource and if you get error code -1073807202, then VISA isn't installed.

Dennis

[Jim West]

I guess I should have mentioned that this is for an installer developed in Installshield.  There will be no LabVIEW code running. 

The installer is checking to see whether NI-VISA is installed on the Computer.  The installer is also verifying the version.

We would like to detect whether NI-VISA, Agilent VISA or both are installed on the computer. 

There are three valid configurations:

• NI-VISA only
• Agilent VISA only
• NI-VISA primary with Agilent VISA secondary

If you install NI-VISA when Agilent VISA is already installed as primary, it will corrupt the Agilent VISA.  The NI-VISA installer doesn't check for the presence of Agilent VISA.  NI doesn't support running as the secondary VISA.  Notably, Agilent will install as a secondary VISA.

If Agilent VISA and NI VISA are installed, then you need to check to see if Agilent is secondary and whether the NI-VISA Tulip setting is on.  To properly install this case, you must uninstall Agilent IO, install NI-VISA, then reinstall Agilent IO.

Our next version of the installer will detect the three configurations and do the 'right' thing.
Jim

[Ebele_Obijiofor]

Hi Jim,

The Registry key is still valid, so you should be able to use that for your check. Thanks!

Regards,