microsoft word - Office 2010 macro issues

I have some macro enabled word documents that worked fine in Word 2003, but in 2010 I cannot get the macro security settings to behave properly.

When I first open a macro enabled document, I get this popup:

At the same time, along the top of Word, just under the ribbon, this bar appears:

After clicking [OK] on the first warning, the "Security Warning" prompt bar dissappears, so I cannot click the [Enable Content] button. This issue occurs even when the file resides in a network location that is trusted. The only fix I've been able to come up with is to enable all macros on all documents, but obviously that isn't the safest way of doing things.

I've tried changing numerous setting combinations in the Trust Center, but still have the same problem. Any ideas?