No new events in system log

I upgraded recently from Vista to Windows 7 in-place.

Every other day, I wake up in the morning to find that my PC has rebooted.

Looking in the event logs for an explanation, I see that my system log doesn't show any new entries since the middle of June. For two months, my system hasn't recorded any new event logs. This obviously started happening while still running Vista.

Any ideas? TIA.

Open event viewer, on the right hand side you will find the "Actions" column, click on properties > Make sure that the enable logging box is checked.

That should do it. Tell me if it doesn't.

Also, are these services enabled?

Thanks for the speedy responses.

Event logging is enabled under Actions on the right side. The event log is also set to overwrite.

The Windows Event Log service is started and set for Automatic.

I just cleared the event log using wevtutil even though I have no problems reading the log.

I should add that although I am not seeing any new SYSTEMS events in the log, I am still seeing plenty of APPLICATION events in the log.

C:\Windows\SoftwareDistribution\ReportingEvents.log

copy and paste that log to desktop.... then you can open and read it tells almost everything tha MS has done to your system. and it also tells if
a REBOOT was required.

good tip. I checked the logs and don't see any system maintenance that required a REBOOT before my seeing the PC restarted.

I'll wait a few days and see how my wevtutil works in getting system logs to spit out useful debugging information.

clearing the system event log with

wevtutil cl System /bu: C:\system.evtx

fixed my problem. I am now seeing events again. The fix was motivated by

Using WEVTUTIL to Manage Event Logs

Thanks to everyone who helped out.