So you can op-out of New League client by a simple method

[4goTTen21]

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[Under construction] (tell me if something looks wrong or seems missing )


Do this with client closed ( check in task manager if there is not running process of League ):

. First, go to the folder above the blue arrow ( "Riot Client" folder)
. And copy the 3 files indicated with orange arrow, to Desktop ( arrow with 3 axis )
. Note I have enumerated the files. Order is going to matter in next steps
. Now, create a new folder on your Desktop and a new text document inside it.
https://i.imgur.com/0oP3Oqu.png
https://i.imgur.com/qBDOfdM.png

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. Go back to the files you copy to Desktop y copy the name of the first one. This way is quicker:
Right click > Rename > Copy
https://i.imgur.com/wzO9bOB.png
https://i.imgur.com/iVWyQ0z.png
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. Back to created folder, open text file and go to File> Save as
. You get save dialog. Select "all files" in the very last drop-down menu
. Then got to the textbox right up there, and paste the name you copied. Append .exe in the end
. So click Save and that will create the first dummy file we need

https://i.imgur.com/gW2kXw0.png
https://i.imgur.com/JeOW3Dk.png
https://i.imgur.com/4kQ2iRS.png

. Do the same with file labeled "2"
. File number 3 is almost identical procedure but, instead of adding .exe, you add .dll
. If you did all right, now you have the 3 dummy files. Now copy that back to Riot Client folder

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. Next, one at time, to the same with those 3 files you just copied back to Riot Client:

Right Click > Properties > Security > Advanced options > Disable inheritance (Select remove to confirm in the dialog box) then apply or save in every window to continue
Repeat with file 2 and 3

https://i.imgur.com/d60SnNQ.png
https://i.imgur.com/mCQ1rWA.png
https://i.imgur.com/wpyGi7u.png

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. Now again, one file at time:
Right click > properties > Read Only and save


https://i.imgur.com/d60SnNQ.png
https://i.imgur.com/asG5BVr.png


And you are done.
I advice you to back up the files left on your Desktop.
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To undo the process, Right click > properties:

. Security>advanced>Add>click the blue text ( the only available option) > Advanced search> Select "everyone" or "all" . That's up to your OS language

. Save everything until all windows close and you are done. Now you can delete or replace the 3 files with your backup ( original) files or simply "repair" client or just update.

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Sometimes New League Client WILL try to repair itself upon startup but will fail. Just ignore the message ( don't push "retry" but click the other button)

[Janitor]

Do you have a video or screenshots of this that you can provide?

[4goTTen21]

All the procedure and final caps of the old client working with today's date but it's all in Spanish

[Janitor]

All the procedure and final caps of the old client working with today's date but it's all in Spanish

It's fine as long as there is some proof of procedure (working).
You can also put sub titles.

[4goTTen21]

Done. Please check it when you have the time

[Dynamite]

I guess this is cool but I can't seem to figure out the reason anyone would do this

[ragnaedge]

what's the effect of this on the client

[4goTTen21]

what's the effect of this on the client

None. It is safe. ( Assuming you ask for potentials damage to League folder )
It acts just by blocking the main launcher of new client, once it can't start, a normal old client launch takes place.
If you are asking what this does, this allows you to use the League client number 2 ( counting from Air client ) instead of New Client