Acrobat X Pro freezes opening certain PDFs

Question

Hi!
Sooooo....  Acrobat X Pro works normally most of the time, but when certain PDFs are opened either by doubleclicking or by right-click Open, Acrobat will freeze and hang.  Reader opens them fine.  I can't distinguish anything unusual about these particular files.  I don't have access to the computer in question much of the time, but I believe the properties said they were created in FileMaker Pro, and said something about Acrobat 7.
The files will open normally in Acrobat X if there is another file already open.
I have installed all current updates and tried changing security preferences.
Anyone seen this problem before?
TIA!
(Windows 7 Pro 32 bit, Acrobat X Pro 10.1.9)

Answer 1

Not using JS console, only at editing JavaScripts to an Action on Text Field Properties.  The script is simple, just checking if the text field's value is not empty and not equal the default value, then save to a new filename.  No circular reference or writing to console...
if ((this.getField("FieldName").value=="FieldName") || (this.getField("FieldName").value==""))
app.alert({cMsg:"Field name is required"});
this.getField("FieldName").setFocus();
else
var FName = this.getField("FieldName").value;
var oMyDoc = "C:\Filename-" + FName + ".pdf";
app.execMenuItem("SaveAs");
app.openDoc(oMyDoc);
this.resetForm();
this.closeDoc(true);
Thank you.