If your standard troubleshooting hasn't yielded positive results with one of these units, there are a couple of things you can do. First, you can clear out their newtek info folder and then reset the config. To do that, open My Computer and select the "D" drive > Media > Clips >. While in the Clips folder, click on Tools at the top of the window, select Folder options, then select the View tab. Make sure Show hidden Files and Folders is enabled. After that you should see a NewTek Info folder. Open it, highlight all of the files in it, then delete them. Close that window. After that, reset config from the splash screen.
They can also try creating and loging in as a new account in Windows.
If this doesn't work, go to Start > Run > CMD > newtekrtme. If they see a ton of repeating k's, that signals a dead VT card. They can try to reseat the card or reinstall the drivers but 99% of the time the card is kaput.
If they don't get a bunch of repeating k's, click on the icon in the top-left (in the title bar) and go to Edit > Find and look for SX and see what it says. . If SX shows then the board is good, I only search for "SX" because each of the aforementioned TriCasters (with the exception of the 100 and the Duo, which are the same) will have a different suffix (i.e. 100/Duo says "SX-3" whereas Studio is "SX-6" or Broadcast is "SX-6 SDI).
If they search for SX and don't find anything, have them search for, "daughter." If no SX entry is found, but there is a daughter entry (ex: Ver 2 Analog Daughter on 0) then the front panel of the unit has most likely died. They can open the unit up and reseat the blue ribbon cables going from the panel to the board. If this doesn't work, the front panel is dead and they will need to go to a legacy repair center.
However if you search for daughter it may say "No analog daughter connected" (if I remember correctly). If that is the case then there will 100% be no SX board detected. If no daughter card is detected it's usually that the floppy power connector is not properly seated on the board, so reseat that connector.
One of the blue ribbon cables may also need to be reseated if the interface comes up just fine but you're missing audio and a video source or you're missing two video sources (in three camera mode on a Studio or Broadcast).
If someone is on a Studio or Broadcast and claims a "random" video input doesn't show up or shows up as black then have them go into the three camera mode (you can do this from the desktop) and see if one of the three inputs is black (it probably will be). That is either a loose cable or a bad VT card or daughter board (they had a combined three video buffers so when you're in six camera mode those buffers get swapped around between inputs which is why you can never see more than three cameras on screen at one time: the old board didn't have enough gusto to process any more video than that)
All this applies to VT, except with VT you couldn't set it to a three cam mode and your SX-8 or SX-84 could have as many as 24 inputs and where TC had pigtail cables the VT had what we called breakout board (BOB) cables which were... 9 (?) pin D-sub cables (looks like a VGA cable)
If anyone ever complained about a black and white input it's cause they're need to configure their input from either composite to component or vice-versa