Can't connect to a server
You start the game and click on Multiplayer, but the server you want to connect to has a red X over the "signal strength" bars on the right
If there are red numbers (such as 1.15) next to the red X, it means you are using the wrong version. Generally speaking, Minecraft requires that you use the same version as the server, those numbers in red.
Here's how to set up a new version-specific profile; this example uses 1.15, but you'll need to be sure to use the numbers in red from the server you're trying to connect to.
- Start the Minecraft launcher
- Click on the "New Profile" button on the lower left
- Change the "Profile name" field to something like "1.15"
- In the middle of the screen, click the "Use Version" dropdown and change it to "release 1.15"
Here I must point out something. If you have a single-player game world with 1.17, BE VERY CAREFUL - do not open that world in ANY lower version. Older versions don't understand the new 1.17 file format - your world as you know it would be gone, replaced by untouched landscape. You may want to keep your older minecraft versions separate, so that the older clients never see the newer worlds.
With this in mind:
- To change the directory for this version of Minecraft, change the "Game Directory" to something like "C:\Users\put_your_own_Windows_username_here\AppData\Roaming\.minecraft-1.17"
- Click on the "Save Profile" button
Ensure that the Minecraft launcher shows "Profile:" set to the newly created profile, then click the Play button.