DB2020 Unlocking Guide With Cruiser Pro Plus

This procedure unlocks red DB2020 phones correctly unlike other tools.
Phones are unlocked in as clean and correct way as possible, by entering unlocking codes by the user.
Reflashing the phone unlocked this way does not cause phone to relock itself unlike phones unlocked by other tools.

Prerequisities:

Be sure to have downloaded and installed all relevant Cruiser Firmware Restore packages for DB2020 phones.
Ensure the phone battery is fully charged.

Unlocking procedure:

Turn the phone on, then by pressing the >*<<*<* "secret" key sequence enter phone service menu. Go to the Service info submenu, then select the Software info item. Write down the first 2 or 3 lines describing the phone firmware version.
Attach the phone normally, preferably via DCU-60 or DCU-65 cable.
Go to the Security RSA tab and press the Unlock RSA button. One server credit will be deducted.
Note: Now the first 768KB of main firmware is overwritten, so it has to be restored or reflashed by a suitable main FW flash file.
Press the Restore firmware button. This operation restores the first 768KB damaged by the Unlock RSA operation provided the respective restoral file is found. If this operation fails, you need to reflash the whole main firmware by the same firmware version as written down in the first step.
Now go to the Locks tab and press the Read codes button. Wait a while, valid unlocking and relocking codes will be shown.
Turn the phone off (e.g. by pressing the <Ctrl-O> key combination).
Disconnect the phone from the cable, turn it on and by pressing the <**< "secret" key sequence enter the phone unlocking menu. Select locked items and enter the respective codes when asked.