I have a Hampton Bay Windward II 54” ceiling fan and fluorescent lamp with remote control. I replaced the original fluorescent circline lamp with a new one. Now the light won’t turn won’t stay on or dim and the fan operates properly. Any ideas?

Sounds like a problem with the ballast of the light. I've heard of problems with these. You'll have to contact Hampton Bay, or take the whole fan back to Home Depot. Here are a list of contacts for Hampton Bay:

http://www.bandwidthcrazy.com/ceilingfans/viewtopic.php?t=45

PS are you sure you used the appropriate replacement bulb?