This URL returns the error: XML Parsing Error: no element found

http://www.stmargaretstl.org/profilepic.ashx?photoUrl=/Portals/0/Users/094/94/94/PSpeth.jpeg

 This URL returns the image:

http://www.stmargaretstl.org/Portals/0/Users/094/94/94/PSpeth.jpeg

Based on other threads I have verified that my default site alias is correctly set to:

http://www.stmargaretstl.org

I have also verified that profilepic.ashx is specified properly in my webconfig file.
It is in fact identical to another site I have (DNN 6.2.4) that is working properly.

Any suggestions would be appreciated.