My default voicemail number somehow changed to *74274, which gives an error message. How do I switch it back to *86? At some point during the past 2 months the drag-down default voicemail number on my Droid X inexplicably changed from *86 to *74274 - a number that returns the pre-recorded message: "Your feature update could not be completed."

How do I change the default voicemail number back to *86?
Try Settings-&gt;Call Settings-&gt;Voicemail. On my Fascinate this pops up with a dialog box where I can enter a new voicemail number immediately. On my EVO (CyanogenMod) I have to go into Settings-&gt;Call Settings-&gt;Voicemail Settings-&gt;Voicemail Number to get the same box, so it's very similar but does take an extra step.