Error after upgrade

Hi,
After upgrading from 1.4 to 1.5 I receive this error and I can’t login anymore :

Fatal error: Exception thrown without a stack frame in Unknown on line 0

Anybody with an advise to solve this problem?

See dev.piwik.org

Magic
Many thanks

In core/Session.php, change:

if(in_array($currentSaveHandler, array(‘user’, ‘mm’, ‘files’)))

to:

if(in_array($currentSaveHandler, array(‘user’, ‘mm’)))

RESOLVED

This isn’t really a fix for the reasons specified in Custom (“user”) session handler using database (ie MySQL) instead of “files” · Issue #1279 · matomo-org/matomo · GitHub

Please refer to 301 Moved Permanently