I said,
at home, I think I have a virtual windows machine
Sorry, I didn’t get a chance until this weekend.
I spun up the VM, and did a fresh install of v7.8.4-32bit. I can confirm your symptoms.
I ran the five experiments I suggested:
Experiment cmd.exe: hmm, the default “Edit With Notepad++” connects to DLL, not EXE. Still, "c:\Program Files (x86)\Notepad++\notepad++.exe" file.nfo crashes Experiment autodetect: turn encoding autodetect off: crashes Experiment 1: remove extension from langs.xml: Fresh RClick is okay Experiment 2: associate with Search Results rather than DosStyle: Fresh RClick is okay Experiment 3: associate with dummy UDL “PlainNFO”: Fresh RClick is okaySo, any of the three experiments which tried to convince Notepad++ that a .nfo file wasn’t MSDOS-Style/ASCII-ART was successful in preventing the crash.
If you do not need the default lexer trying to apply the default color of black on white to all text (ie, doing nothing helpful), I’d suggest implementing one of those three options to get around the buggy interaction between HEX-Editor Plugin and Notepad++'s NFO lexer.