HTC HD7 Secret microSD Card Slot Found [HTC Secretly Put A User-Replaceable microSD Slot In The HD7, In Violation Of The Windows Phone 7 Hardware Requirements]
One of the most bizarre (in our opinion) hardware requirements of Windows Phone 7 that Microsoft makes manufacturers stick to is that it can’t have user removable microSD storage. But, because of the volatile price of RAND flash memory, many manufacturers still are going with microSD cards, but just built directly into the phone. But, the jumbo-sized HTC HD7 secretly has a user-removable microSD slot. Shhhh, don’t tell Microsoft.

The folks at the unwired found the microSD slot on the HD7. Strictly speaking, it’s not really user-replaceable, because it involves some light unscrewing, but inside it is a ‘real’ microSD slot. But, if you were to simply swap out the old card for a new one, you’d get a curt message from WP7 telling you to put the old one back in.
Because WP7 isn’t designed to have user supported memory, it’s designed to use both the ROM and flash storage. But – as the guys at the unwired found out, it doesn’t store any OS functions on the flash storage, so it will run with other flash storage.
Despite the phone initially rejecting the new microSD card, the guys at the site were able to get it to accept the new memory by taking it out and reseeding it in the slot. And then it took the memory.
Keep in mind that this trick involves taking apart your phone (barely), so it will probably void your warranty. But, if you have the hots to put in a 64GB microSD card into your HTC HD7 phone, the instructions are out there.
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