Sub and Function not defined??

My code error is sub and function not defined, when the command Map button is pushed!! Trying to understand VBA, not to sure what that means. My code is below please help!!

Private Sub cmdMap_Click()

Dim cboStations As String
Dim cboDistrict As String

Dim mapDocument As IMapDocument
Set mapDocument = New mapDocument

If mapDocument.IsPresent("K:\TASS\4_MAPPING_DATA_SUPPORT\Traffic_Mapping\District_Maps\2012\Abilene\Abilene_Base_Map.mxd") Then
mapDocument.Open ("K:\TASS\4_MAPPING_DATA_SUPPORT\Traffic_Mapping\District_Maps\2012\Abilene\Abilene_Base_Map.mxd")
ElIf
MsgBox "District Does Not Exist"
End If