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* Press _menu_ on the phone and scroll down using the arrow keys to _-RESET-_-
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* Type the encoded MAC address and hit _menu_ to complete
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Charles Howes created a simple Linux tool called [GSUtil|http://www.pkts.ca/gsutil.shtml] that allows backup and restore of Grandstream Budgetone phones. It should work for the BT-101/102 Budgetone phones, as well as the HandyTone models HT-286 and HT-486, which use the same firmware as the phones.