PDWWorks API GetSpecificDocument

I'm trying to get a single docuemnt from the vault, where Inow its name
useing VB Express I run the following (a connection has alreadybeen established)
Calling the getspecific property method does nothing -no error, andno document return


Dim oldPart As PDMWorks.PDMWDocument
Dim newPart As PDMWorks.PDMWDocument
Dim prop As PDMWorks.PDMWProperty

Dim sz As String

On Error Resume Next


oldPart = pdm.GetSpecificDocument(txtOldPart.Text)
If Err.Number <> 0 Then MsgBox(Err.Description)
newPart = pdm.GetSpecificDocument(txtNewPart.Text)
If Err.Number <> 0 Then MsgBox(Err.Description)
MsgBox(oldPart.Name)
SolidworksApi macros