If a cPanel & WHM server has the system time offset and the clock is skewed by several minutes, this can cause many issues such as SSL errors.
The clock can be synchronized via WHM »Server Configuration »Server Time. Click on the Sync Time with Time Server button to correct the clock.
Note: Some virtualized systems such as Virtuozzo inherit the clock from the host node. These types of systems are unable to change the clock from within the container and must be done on the host system. Specific instructions can be found here: