On 2021 02 06 I had an application refuse to run, presenting with the error "Can't load protection component, OS error 0x7e". What followed was... Somewhat on an infuriating goose-chase.
Honk.

The Fix

The short-story version is: I had to reinstall the vc_redist.x64.exe obtained from Microsoft's latest supported Visual C++ downloads page. As for how I found that out...

Getting to the Fix

Fault of... Neural?

The application presenting the 0x7e original was Neural DSP's fantastic Archetype Gojira. I had it on a trial so I assumed the trial had run out, and iLok was blocking it from being opened. No problem, I expected that. Though... It's weird; I'd never seen that popup or error before. Best check the Archetype Nolly too (for which I do have an active licence) just in case.

It gave the same error.

After a while trying and failing to find Neural-related forum posts on 0x7e, and having a few of my other iLok-registered products fail, I wondered if it might well be iLok's Manager itself that was at fault.

Fault of... iLok?

This led me to discovering the other available fixes for "my iLok License Manager isn't working!", namely:

• make sure the iLok License Manager is up to date
• make sure you're up to date with all your Windows updates
• go to WIN key -> search for Services -> open Services and search for PACE -> double-click -> change Startup Type to Automatic (Delayed Start) or Manual (though this was technically in relation to an error 0x2e)
• turn off all and any anti-virus, anti-malware software and run iLok LM as an administrator
• don't use a VPN
• don't use a proxy

Tried them all, in varying combinations. Still nothing. Same error.

Okay, maybe there's something else going on behind the scenes. Let's go to Firefox and-- Firefox isn't working. Oh, it opens all right. And all my saved tabs are there. But any page I tried to open was blank! Even the config / settings windows wouldn't open.

Firefox is broken too?

By this point I'm very confused, and more than a little irritated; it was working fine just minutes ago. What happened‽ Okay, Microsoft Edge -> Mozilla KB articles then. Let's see if this helps.

• restart Firefox in safe mode? No.
• refresh Firefox? No.
• re-install Firefox? No.

But.

A New Hope

After the second re-installation (maybe I didn't do it right first time, I don't know) I had a new popup. Joy! Progress! But what is?

Ah, promising.

A quick Bing for VCRuntime1401 showed that the issue (at least a version of it) seems to be a common occurrence; according to this marked-answer reply there is a known bug and incompatibility betwen the 2015 and 2017 Visual C++ runtimes. Sounds legit, let's go to that latest supported Visual C++ downloads page and see what happens... Because I didn't have _any VC++ redistributables installed.

Fixed!?

Well... I think so.

Firefox magically started working properly again, and I'm able to open all my iLok-managed products. I'll be keeping an eye on it all, but... This sorted the issue for me.