what's the value of Catagory, is it a field name?
And is there a valid value held by SearchString ?
Also, don't surround it with the single quotes.
Dim MyCommand As New OleDbCommand("SELECT Jack_Name, Jack_Location, IDF_Location, " & _
"Patch_Panel_Number, Port_Number, Cable_Type, Assigned_Port_on_Switch, " & _
"Assigned_Vlan from Cable WHERE " & Catagory & " = '" & SearchString & "'" & _
"order by " & Catagory , MyConnection)