Android Error Fix: "Current version is not available for user. Can't find matched cust for NT-code mcc/mnc[XXXXX],subset[XX]"

If you are like me and enjoy the freedom of an unshackled Android device, you may have come across an annoying error message when flashing a new stock firmware (or possibly an unfixed custom ROM). Normally, this message does nothing, but appears once every time you reboot your phone. While many of us can live with that, I hate seeing that message as it makes me feel like the device I am using is somehow messed up. Today I will give you a quick and easy way to fix this.
Preface
I have only tried this on an international phone. It should also work for European phones. For US phones, or others, you may need to change the portion of code in the note below for your region (e.g. try US instead of EU, etc.).

The Message
The error message is along the lines of "Current version is not available for user. Can't find matched cust for NT-code mcc/mnc[FFFFFF],subset[51]". This is an actual code that I received for my LG G3 when updating to the newest Marshmallow version available.

Everything on the phone worked fine, but the code always came up on reboot. The code refers to a firmware not meant for your phone as it is looking for a region and carrier that it cannot find that it would find on the correct phone. You are probably using something like a US phone and an international firmware, or some other country with the wrong country's firmware.

Fortunately, it can be remedied (for most).

The Requirements
You will need a few things to accomplish this, and if you have this error message, you most likely will have the first or can attain it:

• Root
• A file explorer app
• A text editor
• The specific character sets from the error message.

If you have not rooted your device, you will absolutely need to do this, otherwise this solution will not work. The root procedure for your device will depend on what it is. I would advise checking XDA first, as they will normally have everything you need. If you have a Chinese device--as many of the lesser known models are not in XDA--do a Google search and you should be able to find something.

A file explorer app will be needed to copy and move the file we need to manipulate in order to get rid of the error message. A good free app is ES File Explorer File Manager. This will enable us to do what we need.

A text editor app is needed to actually change the file as it is just text we need to manipulate. You can find tons of free ones on the Google Play Store, and most any should do. Now, you could copy the file we need to your device and then to your desktop. From there you could use something like Notepad++/Notepad 2 if you prefer. But I will be explaining how to do this all from your Android device.

The absolutely most important thing to have is the characters needed to apply the fix. Taking my example above, "Current version is not available for user. Can't find matched cust for NT-code mcc/mnc[FFFFFF],subset[51]", notice there are characters after "mcc/mnc" and "subset" in hard brackets. These are the characters you will need to remember in order to properly implement the fix. The first set may be numbers, letters, or a mix of both. The second set should be just numbers. Of course, you will need to use the characters from your error message, not mine...

The Fix
Here are the steps you need to complete to perform the fix:

1. Open the file explorer app.
2. Go to the root of your device (not storage but to "/").
3. Find and go to the "cust" folder.
4. Find and copy the "cust_path_mapping.cfg" file.
5. Paste it somewhere that you can easily get to on your internal or external storage.
6. Open the text editor app.
7. Go to and open the "cust_path_mapping.cfg" file just pasted in your storage.
8. At the top or bottom, make a space to add a new line.
9. Type in the following: FFFFFF,51=/cust/OPEN_IL   (replacing the characters with your own).
10. Save the file.
11. Reopen the file explorer app.
12. Navigate to where the "cust_path_mapping.cfg" file you just modified and copy it.
13. Go to the root of your device again.
14. Find and go to the "cust" folder.
15. Paste the "cust_path_mapping.cfg" file you modified. (You may be asked to enable Read-Write capabilities, and allow the file explorer to do so or you will not be able to paste the file.) Overwrite the existing file.
16. Reboot.

Note: If your are using a European device, and the above does not work, replace "OPEN_IL" with "OPEN_EU". 

That is all you need to do to fix this error message from appearing on every reboot of your device. This worked for my LG G3 smartphone and should work for most other devices.

Alternative Methods?
There is at least one other alternative method that I know of, but it requires more work. You need BusyBox installed and requires a terminal app.

This is a bit more dangerous because if you mess up the "coding" needed to implement this method, you could cause some major issues with your device. Because of this, I will not document it here.

Power Off
This was a quick article compared to most I publish. I just thought some people would really want to find out how to do this as it has happened to me more than once, an just implies there is a problem (when there really is not).

So enjoy a error message-free boot!