How to switch your Terraria server to TShock or tModLoader

On your server's Overview page, click Edit Server Type, choose TShock, tModLoader or Terraria Vanilla, pick a version, and confirm. The server is reinstalled as the new type. The clean start box is ticked by default and deletes your files, including your world: untick it to keep them.

Download your world and take a backup first, as the panel advises. See How to download your Terraria world and How to back up and restore your Terraria world.

Switch

1. Open your server in the panel. You land on Overview.
2. Click Edit Server Type on the server card. The server type chip at the top of the page, for example Terraria Vanilla, opens the same window.
3. Type: choose TShock, tModLoader or Terraria Vanilla and click Next step. The type the server runs now has the badge Current.
4. Version: keep latest, the first entry and what keeps the server updating itself, or pick a version. Click Next step.
5. Review: read the Terraria note: your worlds are .wld files in saves/Worlds, a folder all three types share, so they are still there after the change.
6. To keep your world, untick Delete my existing files and start clean (recommended). The text under it changes to Your files are kept. If Back up first (recommended). appears, leave it ticked.
7. Tick the box that starts with I understand this reinstalls my server and click Change server type.

The server is offline until the install finishes, usually a few minutes. Then start it.

What carries over

Your settings come along where the new type accepts them: World Name, the join password, MOTD and Difficulty, even though TShock and tModLoader name some of them differently (Server Password instead of Password). A value the new type does not accept falls back to the new type's default. Watch for these:

• World Name with spaces. TShock and tModLoader do not allow spaces, so the name falls back to world and the server would load or make a world called world. Before you switch, rename your world file in saves/Worlds and set World Name to a name without spaces.
• A long password. TShock and tModLoader take at most 20 characters. If your password would be lost, the panel refuses the switch with The new server type does not accept your current server password, so changing now would leave your server with no password. Change the password in Game Settings first, then switch again.
• MOTD. TShock takes 60 characters and tModLoader 40. A longer message falls back to the default.

After the switch

• Check the new type's Game Settings: Terraria server settings: every option explained.
• On TShock, make yourself admin: How to become admin on your TShock server.
• On tModLoader, add mods on the Workshop page, and tell players to join with tModLoader: How to add Steam Workshop mods to your tModLoader server.

When the panel stops the switch

Switching to tModLoader with your files kept, the panel reads your world first. If Terraria 1.4.5 saved it, the window says Nothing was changed: your world is at risk, because tModLoader cannot open it. You can Start clean instead, keep your files and install anyway, or Choose another version. See tModLoader cannot open your Terraria world.

Going back

Switch back the same way: your world in saves/Worlds is still there if you kept your files. A world played on tModLoader keeps its modded items in the .twld file, which Terraria Vanilla does not read.

Good to know

• Choosing the type and version the server already runs is blocked, because it would only reinstall.
• With Try it on a copy first, when it is offered, the switch runs on a copy and your server stays as it is: How to make a copy of your server and try a change on it first.
• The other types compared: Terraria server types compared. General guide: How to change your server type or game version.