Download Update Message in WoW

I tried launching the game today and received the following message:

An updated version of World of Warcraft is available. Please launch the Battle.net app to download the update.

At first, it seemed like everything was normal because as soon as I okay'd that message, a download started. It finished up, said the game was ready, and I tried launching again. Same message. I completely closed down the app and tried launching again. No go. Then I turned to Google and found the following suggestions:

1. From a Reddit post:  Im assuming you are on US server, go into your WTF folder (C: > Program Files(86) > World of Warcraft > WTF) Then open Config.wtf with notepad. Look for "SET portal "EU"" should be at the top. Change EU to US, save it and make sure to restart battle.net or it will just change it back.

I am on a U.S. server, but when I tried this fix, I was already set to US. This didn't work for me. 

2. This suggestion was from a forum post and I wish I had saved the link, but I didn't. Go into your World of Warcraft folder and delete the WTF and Cache folders. 

I tried that and it didn't work either. 

3. This is another suggestion from the WoW forums:  Run a scan and repair. In case you don't know how to do this:

• Open the Battle.net app
• Select the icon you want to fix. This was the World of Warcraft icon for me.
• Click on the "options" icon. This is a little blue cog located underneath the World of Warcraft:  Legion logo to the right of all the game icons. It took me a minute to find this because I kept trying the Bnet drop down menu icon at the very top of the screen.
• In the "Options" drop down menu, select "Scan and Repair" and let it do its thing. It's not a fast process either.

After about 20 minutes of scanning, I got a message from my computer asking permission to allow the app to make changes to my computer. Then another download ensued. Then I got the message that the game was playable. This solution finally worked for me. Not sure what it found and fixed, but the game launched as if new, with the startup movie and everything. 

Maybe either of the first two options might work for anyone else having this problem since they seemed to work for quite a few others but only the third worked for me. Try all three before resorting to anything extreme like uninstalling and reinstalling. Feel free to ask me any questions you might have, but I'm not tech support and only know what I know from Googling it myself. ;)