Minecraft has just been updated and Minecraft Version Changer doesn't have the new version on its list yet.  What do I do?

You can still switch between versions!  Choose an earlier version from the MVC list as normal, and when you want to switch back to the latest version just use the "Force Minecraft to download latest version" option and Minecraft will update itself again to the newest version.

I get an error message when I click on the "Change Minecraft to selected version" button - Why?

Minecraft Version Changer cannot change your Minecraft version if Minecraft is running.  Close Minecraft first, then try again.

Why aren't Minecraft versions 1.2.1 and 1.2.2 included?

For security reasons flippit only includes version files that he has personally sourced from the official Minecraft servers.  These versions were only available for a very short time and flippit was unable to download them before the next release.

I selected a different version but when I ran Minecraft it downloaded the latest version - What happened?

It may be that you have clicked on the "Force Minecraft to download latest version" button during a previous instance of running MVC.  Once this button has been clicked Minecraft will download the latest version on next run, even if MVC is opened again and an earlier version is selected.

Another reason is that Minecraft has been updated to a new version since you last used it, and Minecraft is updating itself to the latest version automatically.  Once the update is complete you can use MVC again to select the version you want to use.

Is Minecraft Version Changer distributing past copies of the Minecraft client?

No! MVC is not distributing working copies of the Minecraft client.  Minecraft cannot be played just by downloading MVC - it will only work if a previously installed copy of Minecraft already exists on your computer.

Only a specific version file from each previous version of Minecraft is included with MVC to facilitate the version change.  Flippit has written to Notch to provide details of Minecraft Version Changer and has offered to withdraw MVC from circulation if Notch has any concerns.