Assuming you have obtained a verified, safe copy of update 301 (not from Megaup), here is the workflow for a modded Switch:
If it fails: The file is corrupt. Delete it and find a legitimate source. Do not try "repair" tools from Megaup pop-ups. update 301 v720896nsp megaup work
Why would someone search for something so specific? The answer usually lies in the realm of scene releases and custom firmware. Assuming you have obtained a verified, safe copy
When a new game update or system patch is released, it often gets archived by the "scene" (groups dedicated to dumping software). However, official distribution channels (like the Nintendo eShop) aren't accessible to everyone—especially those running modified hardware or looking to preserve games offline. If it fails: The file is corrupt
This creates a cat-and-mouse game. Files are uploaded to hosts like MegaUp, but copyright strikes can take them down quickly. A search query like "update 301 v720896nsp MegaUp work" is essentially a distress signal from a user saying, "Has anyone found a mirror for this specific patch that hasn't been nuked yet?"
The second part of your search—"megaup"—is where things get dangerous. Megaup is a free file-hosting service. While not illegal in itself, it is poorly moderated. Here is why searching for firmware there is risky: