element page error

[smcgypsea]

what is an element page, and how do I fix that it "encountered missing source drawing(s)"
Map 3d 2007?
the error box pops up during the opening sequence of the file. It does not register what is missing in the f2 text box. when I hit ok, the file opens as if nothing were wrong. It doesn't seem anything is missing.
probably connected to this problem, the file it is referencing is 'locked by another user' but I have no other files open. And it is detached from both files in which it was referenced.is there any way to fix this?

[Jmurphy]

The "Missing Source Drawing" is either an attached dwg is no longer exists, the alias used to attach it has changed, or a dwg attached to an attached dwg is missing or the alias has changed. Are the source dwgs detached or deactivate?