mini display to hdmi out problems

i didnt think about searching this topic before i posted, i am sorry if this is a popular topic.

i have a mini display port to hdmi adapter that worked fine on my vizio 32' but its too big to use legitimately as a monitor so today i had the opportunity to buy a 26' vizio for 50 bucks and i couldnt pass that up, i plugged the hdmi up to my regular mac book mid 2010. and new tv and it worked fine, im moving this around and i had the display preferences window up and accidentally hit "detect displays" and then the picture on the tv went away and i cant get it back. now that is down at school and i didnt have a lot of time to play with it before i had to come back home and go to work. but it seems like when i pressed the "detect displays" it forgot that it was already hooked up to the tv and tried to find a display and some how blocked my new tv. i havent tried to connect it to a different tv or try another mini display-hdmi adapter

sorry for the long post just wondering if this is a common issue i know that the connection has to be just right to work, but it was working.

it also looks i posted this in the wrong place. i am sincerely sorry.

It's not a common issue.

I think you've identified a few steps to diagnose though, I'll throw some in too:
1. power down and restart your TV and Mac - with all cables disconnected.
2. reconnect and try again
3. try a different cable
4. try a different tv

I unplugged the tv before before I left school Friday so that the internal memory would reset. I will try again on Monday, and will definitely try another tv and adapter

You can also try to "reset SMC" (top google hit for directions).

I'll google it thanks

i just reset the smc, and it worked, thanks a bunch guys.