You Can Use The Below Method For Upgrade HTC desire 300/301e /And If You Want To Hard Reset It By Flashing The Stock Rom/ In Case If You Are Using Any Custom Rom And Want Back To Stock And Official Firmware Or Facing The Bootloop Problem. This Method Is Also Useful For Sudden Death/Bricked/Not Power And Also After Flashing The Stock Rom imei Null or Unknown Baseband Problems Can Be Solve.

1. First unlock bootloader follow the instructions here.

2. 2 / flash CWMRecovery_Philz-cmw6-v5.15.9_base_6.0.3.7_by_SPaWn.

3.flash this rom via recovery HTC_Desire_300(Zara mini)_stock_odex_1.10.401.4_root_updated_v.1.0.1.zip.

Source: http://suadt.com/
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You Can Use The Below Method For Upgrade HTC desire 300/301e /And If You Want To Hard Reset It By Flashing The Stock Rom/ In Case If You Are Using Any Custom Rom And Want Back To Stock And Official Firmware Or Facing The Bootloop Problem. This Method Is...