CISCO 3500 Series problems

I have several Cisco 3500 series Inline Power switches and all the lights are blinking in unison???? The problem seems to be generated from the two Gig ports.. one having a fiber run to the core and one having a gigastack linking to the other switches in the same closet....

Any Ideas????

what problem are you having, other than the LEDs blink in unison? Is there some kind of performance problem? does the switch pass any traffic?

LanMan,

Does the link going to the other switches in the closet return back to the core switch ?

Have you got STP configured to avoid possible loops that might be present?