You may want to change the default document class depending on the type of documents you mostly work with or your organization requirements as each document class has it own security level, required profile fields, and other settings specific to the class. For more information, see the Document Classes section in iManage Work 10 Server Administration Guide.
Open the imWorkOptions.xml file in a text editor, and search for the key name iManage.Import.DocClass to locate the following text:
<key name="iManage.Import.DocClass" value="DOC"/>
Change the key value from DOC to <document class>. For example, E-MAIL.