Lmcq Auth Model Decryption

If someone sold or shared you an encrypted .enc-style checkpoint made with LmcqAuthModelEncryption, this is the node that opens it back up into a usable MODEL/CLIP/VAE trio - the same three outputs you'd get from a normal checkpoint loader. Everything downstream (KSampler, CLIP Text Encode, VAE Decode) wires up exactly like it would for an unencrypted checkpoint; the encryption is invisible past this one node.

The two fields you'll actually fill in. model_name is a dropdown of encrypted checkpoints sitting in your models folder - pick the file you were given. model_password is the string the creator encrypted it with; get it exactly right, including case, or decryption fails. That's genuinely it for user-facing configuration - there's no machine-code field to fill in on this side, because if the file was machine-locked at encryption time, the check happens automatically against the hardware you're running on, not something you enter.

What's happening under the hood. Per the README, this Auth family is built around a cloud authentication server LMCQ runs - decryption can involve real-time validation against that service (checking machine binding, usage limits, expiration) rather than being a purely offline password check. That's the tradeoff versus the pack's simpler "Runtime" family (LmcqRuntimeModelDecryption): Auth decryption may need network access to LMCQ's platform to succeed, which the Runtime nodes don't.

Installing it. Through ComfyUI Manager (search "ComfyUI-LMCQ") or manually:

cd ComfyUI/custom_nodes
git clone https://github.com/sebord/ComfyUI-LMCQ

Restart ComfyUI afterward. This node itself has no extra downloads - whatever model you're decrypting is the only file you need beyond the pack itself.

Where this actually breaks, and it's a real, reported problem. The single most common failure with this entire pack isn't a wrong password - it's the node not showing up at all. There's a documented ModuleNotFoundError: No module named '...ComfyUI-LMCQ.runtime.api_model_protection' bug that fires on import, because the Auth encryption/decryption nodes rely on a compiled, obfuscated protection module that's gone missing on some installs. Because that failure happens inside the pack's shared __init__.py, it takes down the entire pack's node registration at once - you won't just be missing this node, you'll be missing every Lmcq node, including ones with nothing to do with encryption. This has been reported on r/comfyui by multiple users hitting exactly this trace while trying to use Flux NF4 loading (which shares the same __init__.py), with no working fix found in that thread at the time. The pack's own README added a fix in its January 2026 changelog: copy the Python-version-matching files from the runtime directory into the runtime root, delete the mismatched ones, and restart - worth trying before assuming your install is unsalvageable.

If the node does load and you're still failing to decrypt, the ordinary culprits apply first: a mistyped password (copy-paste it rather than retyping), a file that got corrupted or partially transferred, or - if the creator machine-locked it - running it on hardware whose machine code was never added to the authorized list. If it's the last one, there's nothing to fix on your end except asking the creator to add your machine code (from LmcqGetMachineCode) and re-issue the file; a mismatched machine lock can't be worked around locally by design.