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[Solve in 3 steps!] packet 6 bytes shorter than expected – mysqlnd cannot connect to MySQL 4.1+ using old authentication

Posted by .: Pampa :.

Weird, huh?

I'll explain you in 3 steps how to solve it! (trust me!)

Ok, I thought the same than you when I get this message.
I had a script that makes two connections to two servers.
I was using the "second" server from my client application and it was working perfectly, so what happened!?

I've read many posts that said me to re-install PHP and or MySQL. What the heck!? No way!
Those are production servers, tenths of thousand kilometers from here, and are working. I simply can't.

Ok, here is the short 3-steps guide (then will explain you why)

1. Turn off the old_passwords compatibility in MySQL

2. Recreate the password for the user

3. Check for the new password's length (must be 41 instead of 16 and it hast to start with an asterisc)

4. Breath again :)

Ok, but WHY?
I'm not going to burden explaining why PHP is not compatible with the old_passwords hashing method.
If you want to know the truth then you can Google for it.

Just let me tell you that simply creating a new user or a new password will not solve your problem until you don't turn off the old_passwords BEFORE changing it.

Hope this helps!

Pampa