[TYPO3-english] Migration 4.6 to 6.2: error "Could not acquire lock for ClassLoader cache creation"

[François Suter]

Hi all,

I'm trying to upgrade a TYPO3 site from 4.6 to 6.2 (using current 
master, i.e. 6.2.1-dev). I've been through the steps recommended in the 
Installation Guide and I'm now trying to start with the actual upgrade: 
so  I've changed the symlink to point to the 6.2 source and try to 
access the Install Tool. I have then 2 problems:

1) I get redirected to the "start" script (i.e. 
typo3/sysext/install/Start/Install.php), which shouldn't be the case 
since I already have a configured database.

2) that page is blank due to the following error:

"Uncaught exception 'RuntimeException' with message 'Could not acquire 
lock for ClassLoader cache creation.' in 
/usr/local/src/typo3/typo3_src-6.2-dev/typo3/sysext/core/Classes/Core/ClassLoader.php:723"

Does anyone have hint what might be the cause of such symptom? In which 
direction should I dig?

Thanks in advance for any hint.

Cheers

-- 

Francois Suter

Work: Cobweb Development Sarl - http://www.cobweb.ch

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