In order to hard reset a BenQ-Siemens E52, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
BenQ-Siemens E52 device will be brought back to the default configuration of a brand new device.
1. Switch on the phone.
2. Type this in: *#9999#
3. The phone will now restart. Yaay, the hard reset is complete.