In certain cases, MEGA.NZ shows "undecrypted files" or "undecrypted folders" and it seems impossible to access them. I seems to happen, when there are multiple users involved:

  • User A creates a folder and shares it with User B and C. (Full access is granted in order to enable using the SyncClient on Windows.)
  • User B creates a sub-bolder (or file) in the shared folder.
  • User C gets this new file or folder displayed as "undecrypted" (in the web interface)
  • At the same time, user A can access it normally.

The undecrypted file or folder is invisible to the Sync Client. Nearby the undecrypted folder, MEGA indicates, that it would be decrypted as soon as the key would became available, and this would happen, as soon as the owner of the file or folder logs in again. But this seems to be not correct. I've seen that all the users (A, B, and C) are logged in at the same time, and it still shows the entities as undecrypted.

Actually, as soon as User A moves the file or folder to another location, it gets decrypted.

Currently I work around this problem in the following way:

  • After user B or C uploads something, he has to call user A on the phone.
  • User A moves the item to another location and back to its original location again.
  • Then it is available for all three users.

I don't like phone calls to announce that a new item is available in a shared folder.

Is there any way to do this more easily?

3 Answers 3


I am running into similar issues and i have already contacted the MEGA's support center. I will come back with more details when I get a response.

I'm only able to reproduce the problem with a folder that has some messy history, namely sharing between multiples accounts, being edited by several accounts, changing sharing privileges, uploading files using different browsers/MEGA apps, etc.. In my case User C is not an account just an access made through a browser using the folder's link.

However, I'm not able to reproduce the problem if User A creates another folder in his MEGA Cloud's root. Therefore, I suggest doing this and, if it works well, move all the files you need in this new folder. This is more of a workaround, but I hope it helps you.

[EDIT:] I have been in touch with the MEGA's support center. They were not able to reproduce my problems, therefore had no way to help me, however one of my problems seems to be gone since the last update of the MEGA's Firefox extension (v3.20.5).


It's most likely a fallback protection against misuse by having multiple accounts share their contents with one master account bypassing the space quota limitation.

I've tried to import the shared the folder into a different account by using its exported link and decryption key, and all I found were the same undecrypted files. I've managed to redress the issue by removing the shared user of the folder and the exported folder immediately "decrypted".

The op's hypothetical is pretty hyperbolic...

One can mess with megacmd and exported resources. Make a script or app which polls from a shared pool, be it email or other cloud drives, btsync should work just as well in dealing with small data like links. The data polled will be the shared links including decryption key. When one party uploads, he exports it and places the link in the btsync app, from there it gets sent and the other parties involved just need to import it into their own drives. That's the freeware version.

Other than that most likely paying for the service will unlock it fully, including a more helpful support staff.

As for using the SyncClient, it does not restrict multiple logins to one account, you can have it on many machines and devices and all can be logged in with one account, thus multiple accounts and shared folders are not needed.


undecrypted file error message

Had this error: "This file will be decrypted as soon as the cryptographic key becomes available (when the share creator logs in again)."

This message is completely useless, as already mentioned by @caenrigen. Looks like nothing has changed in the last 3 years. This shared folder of mine also had kind of a messy history, so this seems to be the trouble maker.

At least the workaround works: Created a new root folder and moved everything there. Now Person A and B have full access while everyone with the sharing link can view the content. Until now, everything Person B had uploaded, was "undecrypted".

Edit: Some days later it's broken again...after my friend started using the desktop app (again)