SOLVED the following : Needed to close vMix Inputs that were also using the DeckLink even though they were not in the active Preview or Program. This freed up the resource to be used as an Output through external.

I Need help with getting External Outputs from vMix to Decklink Duo. I can't get output from the DeckLink Duo from vMix. I can get 4 inputs into vMix from the DeckLink Duo (1-4) with no problem. In the vMix settings I tried both the standard DeckLink Duo (1) -(4) , as well as the DeckLink Video Render (1)-(4) and only errors. On the PC 2 with teh Decklink SDI 4K I have no problem with vMix External using Decklink Video Render to get SDI output from the card. Just notching is working for me on the Duo.


Setup:
PC 1
vMix Pro 26.0.0.45 x 64
DeckLink Duo / Desktop Video software version 12.7.1
NVIDIA Quadro P4000

PC 2
vMix Pro 26.0.0.45 x 64
DeckLink SDI 4K / Desktop Video software version 12.7.1
NVIDIA GeForce GTX 1080Ti

BMD 2/me


1. vMix External set for Decklink Duo (2) - Set each channel to be linked to single Ports. Connected the correct output port to the following:
a. Input on a BMD 2/me
b. Input on a BMD DeckLink PCI 4K on a second PC running vMix
Both resulted in the same error from vMix and no output. Nothing shows on the Desktop Video interface except my functional Input 1

2. attempted the above with different ports - same results

3. attempted the above using DeckLink Video Render (1)-(4) as another option, but this also resulted in errors.

4. Restarted 3 times ( ...when in doubt... :) )

I must be missing something simple. All help appreciated . - Thank You. I will post whatever results in Success here once this is resolved. - Paul