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June 13th, 2011 Question by dvsboriqua07: How do I unlock my HTC Aria, so i can download non-Android Marketplace apps?
I want to download apps online with out acquiring the stupid message that says “Install blocked: For security, your phone is set to block installation of applications not sourced in Android Marketplace”
Very best answer:
Answer by John
All HTC models including HTC Aria can be unlocked making use of htc unlock codes. This is a guaranteed strategy which very quickly unlocks a HTC mobile phone.
http://www.htcsimunlock.com
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You could try rooting the phone and installing a custom rom and that might solve the problem.