ChevronWP7 unlock for Windows Phone 7 devices enables users to install custom and home
brewed .XAP files / applications that other wise won’t be possible. However, no matter how perfect the unlock tool for WP7 is, there was a probability that Zune will relock your phone once synced.
Folks over at XDA finally have a solution through which you can prevent any Windows Phone 7 Devices [included WP7 ROMed HD2] from losing the unlock once synced with Zune. This hack for now is only applicable on HTC Windows Phone 7 handsets, but we believe that support for other brands will be added in near future.
Here are the step by step instructions on preventing Zune locking your WP7 device after ChevronWP7 unlock is deployed.
The first step is to download TouchXplorer Zip file from here and extract the XAP file.
Once you have the XAP file extracted, install in on your Windows Phone 7 device.
Now download HTC Connection Setup For Windows Phone 7 and install the xap on your WP7 device.
Now launch TouchXplorer on your handset and follow onscreen details to copy \ MyDocuments \ My Ringtones \ CustClear.provxml to \ Windows \.
Once done, launch HTC Connection Setup on your device and tap on the check button to let it provision.
And there you go! Now connect your phone with Zune and you won’t be facing the unlockdisability anymore. You can head to the official XDA thread posted here for further details and support.