Fixing 7DtD Version Mismatch
When players see "version mismatch", the fix is an update from the Admin tab - not a restart.
What Causes Version Mismatch
7 Days to Die clients update themselves through Steam. When The Fun Pimps publish a patch your players get it automatically, and a server still on the old build refuses them with "version mismatch".
Your server does not follow along on its own unless auto-update is switched on. And a plain stop-and-start does not pull a new build either - it relaunches the files already on the host.
Fixing It on GameGrid
1. Open your server and go to the Admin tab.
2. Look at the Game Updates card. It names the build your server is running.
3. If an "Update available" badge is showing, click "Update now".
4. The platform backs the server up, warns anyone playing with a five-minute countdown, stops it, moves it to the new build and starts it again. An empty server skips the countdown.
5. Watch the card. It is rewritten with the real outcome when the work finishes, including the error text if it fails.
While you are there, turn "Automatically apply game updates" on. That is what stops this happening again.
No Update Is Offered Yet
The platform polls Steam for new builds every five minutes, so a patch published a moment ago may not have been picked up yet. Give it a few minutes and reload the Admin tab.
If the card says the running build "has not been reported yet", the host has not checked in since. That fills itself in; it does not block an update.
If your players updated but Steam has not published a new dedicated-server build, there is genuinely nothing to apply. That happens when a client-only patch ships, and it resolves when the server build follows.
It Is Still Mismatched After Updating
Have the affected player close Steam completely and reopen it. That forces the client to re-check for its own update.
Check the player is not on a Steam beta branch. Right-click 7 Days to Die in Steam, Properties, Betas - it should say None. GameGrid runs the public stable branch and there is no way to move a server onto experimental, so a player on experimental cannot join.
Compare the numbers before you open a ticket: the build on the Admin tab's Game Updates card, and the version in the player's 7 Days to Die main menu.
If they still do not line up after both sides have updated, open a support ticket with both numbers and your Service ID from the Overview tab.