So you can reinstall. If you have the original configuration you can install it as you did originally. If you don't have it, you should contact your VPN service provider to get a new copy, then install that. That is probably the best solution, especially if you have many configurations, because this problem probably affects all of your configurations.
There is an alternative that might work if you an admin on your computer. If you don't know if you are an admin, then you probably are, so go ahead and try this. First, copy the following (it should all be on one line), then paste it into Terminal:
sudo chmod 644 "/Library/Application Support/Tunnelblick/Users/sueevans/MPN GBR.tblk/Contents/Info.plist"
Then press the "enter/return" key on the keyboard.
You will be asked for a password. Type your computer password and then press the "enter/return" key on the keyboard again. Noting will show up as you type your password, not even asterisks or bullets.