Find Visa Resource doesn't find all

[Dekay]

I had been using VISA Find Resource to get a list of instruments attached. It worked fine until updates. The SW was developed to use various instruments (temperature controllers) for the same function. VISA Find Resource was used to get the list, and then a comparison to possible instruments was made to determine which command set to use.

After updating, the function no longer returns any instrument. They are listed properly in MAX, and communications in MAX works fine, and in the programs with the address string specified explicitly.

It does find Com ports if 'Include Matching Aliases' is selected for search mode. 'Expression' for search is left blank, default is '?*', which should be all.

The Question: Any ideas on why the VISA Find Resources Function does not return anything? Help for VISA Find Resource Function states " If a resource does not appear in the list, you can explicitly add the resource in the NI-VISA configuration utility, such as Measurement and Automation Explorer..."  However, the resource shows up in MAX. Is it a config detail issue? 

Windows 10, LV 2012, MAX 15, shoe size 11.5.

[crossrulz]

---

@Dekay wrote:

It worked fine until updates.

---

What updates were done?  How are the instrument connected (Ethernet, GPIB, serial, etc.)?

[Dekay]

Not so much an update as a reinstall. Had periodic disconnects in the communication with the temperature controller, so reinstalled all LV software. Previously, before reinstall, NI Configuration Manager would be stopped when MAX was launched. Now it remains running, as it should.

The temperature controller is connected via Keysight USB/GPIB adapter. That may be a possibility for for the problem. My guess would be a simple configuration error somewhere, either in Keysight or MAX, but I don't know what.

I have Keysight installed as secondary VISA, and 'use 488' box checked in the Keysight IO Library (2018). Tulip passport is selected in MAX. All the right NI resources are running in Windows.

The example "Show All Hardware.vi" also works fine. I can switch to that, but it seems that the error preventing VISA Find Resource may dog me later.

Thanks for the help.