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Mike, Mac Medic
Category: Mac
Satisfied Customers: 8994
Experience:  Over 20 years IT experience with Apple computers in publishing, marketing and design.
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I am having a problem with connecting my macbook pro to my

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I am having a problem with connecting my macbook pro to my tv with HDMI. Every time I connect it, it says resolution mismatch. I have tried connecting my mac book to all my other tv's and it woks fine. i have a 39 inch magnavox tv. this is a problem because i use my mac book in clamshell mode 98% of the time.

Try this with the MacBook while connected to the TV:

1. Shut down the computer.
2. Locate the following keys on the keyboard: Command, Option, P, and R. You will need them in step 4.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys before the gray screen appears.
5. Hold the keys down until the computer restarts.
6. Release the key
Customer: replied 4 years ago.

I'm sorry, I forgot to mention I rest the PRAM yesterday and that did not work. I have also already deleted the "Windowserver"files

Please go to the Apple logo on the upper left of the screen, go to About This Mac (DO NOT Select More Info), and tell me the Version (under Mac OS X), the Processor and the Memory, it is all right there.
Customer: replied 4 years ago.


Processor: 2.3GHz intel core i5

Memory: 4GB 1333 MHz DDR3

When you go to System Preferences/ Display and select Scaled what resolutions are listed?
Customer: replied 4 years ago.

when its connected to the TV:













What model MacBook is it? Can you give me the serial number?

Customer: replied 4 years ago.

Macbook Pro 13 inch, Early 2011

OK what model Mini DisplayPort to HDMI Adapter?
Customer: replied 4 years ago.

Rocketfish RF-AP305

It seems that should work. You say you have connected it to other Tvs and it works at 1080p or 1080i?
Customer: replied 4 years ago.


OK that kind of rules out the MacBook but lets try resetting the SMC:

Resetting the SMC on portables with a battery you should not remove on your own
1. Shut down the computer.
2. Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
3. On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
4. Release all the keys and the power button at the same time.
5. Press the power button to turn on the computer.
Customer: replied 4 years ago.

it is still giving me the message "this tv does not support the output format, video resolution, or refresh rate of connected Device"


OK I have had that message a few times in the past and unplugging the TV/ Receiver or other device from power and allowing it to "restart" has fixed it. Try that.
Customer: replied 4 years ago.

it is still only working when that laptop is open but not in clamshell mode

OK I didn't get from your question that it worked at all. So it works but ONLY when not in clamshell mode?
Customer: replied 4 years ago.
Yes I'm sorry I wasn't clear about that before
Do you have a mouse and keyboard attached when you close the laptop?
Customer: replied 4 years ago.
Yes I have a Bluetooth keyboard and mouse connected
OK there must be a problem with the HDMI "handshake" with that TV. Did you try unplugging the TV from power after you closed the MacBook?
Customer: replied 4 years ago.

Yes several timas

OK short of reinstalling Mountain Lion (which you might try but since it works with other TVs I doubt that will work) I suggest you contact the manufacturer some newer TVs have firmware that can be updated. Sorry I wish I had a better answer but we have tried everything else.
Customer: replied 4 years ago.

would reinstalling mountain lion delete all my files?


Reboot and hold the Option key, select the Recovery HD to boot from, then run Disk Utility and when it opens you will see your hard drive (usually Macintosh HD) on the left. Highlight your hard drive and click on Verify Disk on the right. If that is OK and only if that is OK click on Repair Permissions. If Verify Disk is not OK try to Repair. If Repair is successful then Repair Permissions if it is not successful let me know.

If all is OK quit Disk Utility and select Reinstall Mac OS X. It will take a while to download. Let me know.
Customer: replied 4 years ago.

hello, so last night I reinstalled mountain lion and that did nothing to help. Today I was using my macbook outside, and when I brought it back inside and connected it back to my TV it worked for a moment in clamshell mode and I could use the screen, but then It went right back to displaying the " resolution mismatch" box.

Yes I'm afraid it is the TV there are different HDMI standards maybe a different cable, I suggest you ask the manufacturer what standard the HDMI is on the TV I don’t see it on the site. If that does not work and you plan on using that a lot with your MacBook I would return it if possible and get a better TV, sometimes you get what you pay for unfortunately.
Mike and 5 other Mac Specialists are ready to help you
Customer: replied 4 years ago.

yes unfortunately we do. Thank you so much for all your help.

No problem good luck.