The Samsung Focus is a good Windows Phone 7 device but unfortunately it is also known for its microSD card slot issues. Users have for example reported some lag problems while using microSD cards. But now thanks to wm.andrew.wilson @ XDA it is now possible to fix those problems using some registry edits.
Please note that we won't be responsible if you end up bricking your device. Rooting or customizing your device can be risky, if you follow the instructions you should be fine!
The problem seems to be linked to some power management issues in the Samsung drivers as you can see below [from SD card issue fix - Need testers!]:
A few of us on the SD card list thread have tried this and it seems to be stablizing things....the theory as we are working with now is that the problem is due to a power control issue in the Samsung drivers for the phone, not especially in the card itself.
No ill effects have been reported as of yet, and the battery life seems to be on par with before the switch was made. It is a simple fix, and can be reversed easily.
I ran the phone for 2 months without a card, and with these keys toggled, it is actually FASTER than it was. I don't fully believe it, but it has been over a week and rock solid.
Before you can apply this fix you will need to unlock your Windows Phone 7 device, you can follow our article @ How to Jailbreak Your Windows Phone 7 Device.
Then you will need to install the Registry Editor, you can find it @ http://forum.touchxperience.com/viewtopic.php?f=20&t=593#p2390.
Finally change the following registry keys:
- HKEY_LOCAL_MACHINE>Drivers>SDCARD>ClientDrivers>Class>MMC_Class
>DisablePowerManagement (Change to 0) - HKEY_LOCAL_MACHINE>Drivers>SDCARD>ClientDrivers>Class>MMC_Class>High_Capacity
>DisablePowerManagement (Change to 0) - HKEY_LOCAL_MACHINE>Drivers>SDCARD>ClientDrivers>Class>SDMemory_Class
>DisablePowerManagement (Change to 0)
Reboot your phone and you should be all set!
You can get more information @ http://forum.xda-developers.com/showthread.php?t=938415
Don't forget to follow us on Twitter and join our Facebook Fan page to stay updated.