Issue: Tried to upgrade and got error

Okay, so this happens when:
1. You're performing a fresh installation, OR your previous version is lower than Gamma 4 (common since Gamma 4 is the new version).
2. Your forum software is XenForo.
3. Your server has high load, is shared with other users, or throttled in such a way that installing 2,000 phrases cannot be completed in less than 10 seconds.

The result is a database error that a phrase was already installed, even though it wasn't. This is now fixed in build 005. If you download it again, you shouldn't have any more problems like this for phrases.

I'm getting the exact same error with vB4:

I'm doing a test install using vagrant, so there's no load on the server.

In vault/core/controller/cp/install/vw.php, I changed line 27 to $MIN_PACKET = 3*1048575;

Should I change a value in my.cnf?

Added max_allowed_packet = 32M to /etc/my.cnf and things worked flawlessly.

Changing the MIN_PACKET requirement setting in vBulletin will not work. It now calculates what it needs to be to avoid getting a database error when vBulletin rebuilds the phrase cache. Thus if it says the lowest compatible is 3.00M, then you need at least 3M in /etc/my.cnf. I find it odd that the error message is talking about versions though...

When this issue was first opened the default values in the requirements were too high, but they have since been lowered and actually calculate based on your database size.