[Dolibarr-user] Update issue

[Torsten Appelhagen]

Hello,

today I wanted to update from 5.0.1 to 6.0.0.
I downloaded the archive, unzipped and uploaded everything to the 
existing folders.
Now Dolibarr should take me to the upgrade script on next login, but it 
doesn't! When calling /install manually, I am told my last version is 
5.0.1 and the current one is 5.0.1, so "update 5.0.* --> 6.0.*" is 
greyed out.

Am I doing something wrong? I'm quite sure I always did it this way...
How/where is the current version detected? The only definition I was 
able to find is in filefunc.inc.php but it's only executed in case 
DOL_VERSION is not already set before (and seemingly it is).

BR
Torsten