Add a custom field of type = file.
Add that field to the sample data profile gid=1 (Name and Address)
Edit a contact record via the profile and upload a .jpg (example: civicrm/profile/edit?reset=1&gid=1&id=55)
Go back to edit the same record (profile/edit)
Click "Delete Attached File" (goes to this url: civicrm/file?reset=1&id=2&eid=105&action=delete&confirmed=1)
Fatal error is thrown:
"Sorry. A non-recoverable error has occurred.
is not of the type Integer"
Relevant portion of backtrace:
/Users/dgg/svn/trunk/CRM/Core/Error.php, backtrace, 245
/Users/dgg/svn/trunk/CRM/Utils/Type.php, fatal, 241
/Users/dgg/svn/trunk/CRM/Core/DAO.php, validate, 757
/Users/dgg/svn/trunk/CRM/Core/DAO.php, composeQuery, 714
/Users/dgg/svn/trunk/CRM/Core/BAO/CustomField.php, executeQuery, 1106
/Users/dgg/svn/trunk/CRM/Core/BAO/File.php, getTableColumnName, 169
/Users/dgg/svn/trunk/CRM/Core/Page/File.php, delete, 65