This error occurs when a xml file has been malformed or generated wrong.
Open you Contact.object
file and remove all white spaces before
<?xml version 1.0...>
tag. You cannot add space before starting tag of a xml
file.
Update:
Basically these these type of error are very hard to find.
The easiest way way get you previous working copy of that file and compare it,
If you cant do this then the only way is:
Read the xml proc-types is it in correct format or not . proc-types
Check for all tags ate they started and closed properly?
Are their same unprintable characters (Notepad++ will help in that) also what are the unprintable characters for an xml file? Here is answer
That the only help we can provide. Also if it is possible to post that xml file then we could help some. Salesforce object files have fixed format which should be maintain to save that file properly means <fields>, <listViews>, <searchLayouts>, <actionOverrides>
in <CustomObject xmlns="http://soap.sforce.com/2006/04/metadata">
tag.