Windows Phone 7 - no DIY SD cards, says Microsoft

Microsoft Phone 7 users have been warned not to upgrade handset memory or use the phone’s SD card in other devices, after it emerged that the handsets alter the memory card’s format.

According to Microsoft, removing the original SD cards can cause data loss and stop the handset from working properly, limiting upgrade options that might have been a key purchasing motivation for media hoarders.

“You should not remove the SD card in your phone or add a new one because your Windows Phone 7 device might not work properly,” Microsoft said on its support site.

“Existing data on the phone will be lost, and the SD card in your phone can't be used in other Windows Phones, PCs, or other devices.”

The company said that when an SD card is integrated with the operating system, Windows Phone 7 reformats the memory card, and creates a single file system that spans the internal storage and the card, locking it to the phone with an automatically generated key.

Because of this, handset memory was never intended to be end-user expandable in Windows Phone 7, stating that the SD card slot was intended for use only by manufacturers and mobile operators.

To reinforce this position, Microsoft said it would disable handsets when consumers removed pre-installed SD cards.

“If you remove an SD card that has already been integrated with the phone, the phone displays an error message that tells you to reinsert the SD card,” the company said.

“All phone functionality is disabled except for the ability to make emergency calls. The phone will function normally again only if you reinsert the original SD card and then start the phone.”

Users can, according to Microsoft, only insert a new SD card before the handset is first turned on or by restoring the handset to factory settings, which would cause data loss.

Microsoft warned that even if a phone appeared to be working properly after the upgrade, problems could arise once the internal memory had filled up.

“In some cases, these performance issues might only be evident after using the phone for some time,” Micorosft support said.

“For example, if your phone has 8GB of internal memory and you integrate a non-compliant SD card with the phone, you might notice the performance issues only after the 8GB of internal memory is filled with applications and media.”

This article originally appeared at pcpro.co.uk