Implicit conversion from data type sql_variant to varbinary(max) is not allowed. Use the CONVERT function to run this query.

Hi,
Im  trying to upload  image  using  file upload  in formview  it giving me the error 
<asp:FormView ID="FormView1" runat="server" DataSourceID="dsWorkRequests" DataKeyNames="ID" DefaultMode="Edit" Width="100%" OnItemInserted="FormView1_ItemInserted" OnItemUpdated="FormView1_ItemUpdated"> <ItemTemplate> <div class="leftcol"> <div class="content"> <h2 class="title">Contact Information</h2> <table> <tr> <td align="right"> <label for="ddlClient"><strong>Client:</strong></label></td> ...