My htc hd2 over heats often,and when i make a call or receive one,i cant hear anything.

The fact that the mic is working when your receive a call, mean that the mic is working. I recommend taking your phone to the nearest Care centre and ask them to "flash" your phone.
This seems like a software problem.
That procedure can wipe all data from your phone so please backup your phone to your pc before you take it in.

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Hello Sly,

The HTC HD2 Smartphone may be affected due to virus or malware which is causing restarting and screen freezing problem. The virus or malware can infect the HTC HD2 Smartphone by the means of Bluetooth or PC Connectivity. To disinfect or remove the virus from the HTC HD2 Smartphone or from memory card it contains, scan your memory card using the anti virus installed in your machine.You can scan you memory card for antivirus using the Avira anti virus.Please download the anti virus from :

http://www.avira.com/en/free-download-avira-antivir-personal?

Download the .exe file from the link.

Install the software in your computer.Remove the memory card from the phone and connect in your machine using the memory card reader and scan the card for viruses or malwares.

download an htc sync update or anything similar from the official htc website.
it is probably located at some sort of support service in the website.

Contact T-Mobile support - 1-800-T-Mobile. They will have to direct you to the correct ROM

i have an Htc too you must synchonize your htc to your pc or laptop, try to go to their website and get the software

it seems you may have activated call barring try unlocking it, if not then the issue may be with the phone,
let me know how it goes.

Well for your information microsoft wm 7 so far is not coming to Htc hd2. But if you want to enable the 567MB Ram then you have to flash your phone with the After market cooked roms. You can go on xda-developers.com and click on the forums choose Htc hd2 and then rom developments. If you need any futher help let me know thanks.