Redmine

Buonasera,
ho appena installato la Redmine e spesso mi viene fuori questo errore:

Internal error

An error occurred on the page you were trying to access.
If you continue to experience problems please contact your Redmine administrator for assistance.

If you are the Redmine administrator, check your log files for details about the error.

come lo posso risolvere?
Grazie
Luca