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What you may need to do, is download the Magellan content manager software from here.
Once downloaded and installed, you need to connect your Magellan to the computer, run the Magellan content manager software and have it install any software updates it finds.
Then, restart the Magellan by sliding and holding the power button for 10-15 seconds.
Then test and see if the address book will work normally.. If not, we may need to go into the Magellan through your computer, and delete the old corrupted address book file.
So let me know whether this works or not once you've had a chance to try these steps, thank you.
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