Error: Unable to read beyond the end of the stream - vb.net

Question

I have this VB code which is giving the above error in the code below
Try
'Job Ticket Section
StatusText = "Reading Job Ticket Data."
FileName = System.IO.Path.Combine(SoftSavePath, "cfgjt.sys")
If Not System.IO.File.Exists(FileName) Then
CopyDefaultSoftJobTicketItems(FileName, ErrorFlag)
End If
filenumber = FreeFile()
FileOpen(filenumber, FileName, OpenMode.Binary)
.ConvexJobTicketItems = GetConfigConvexJobTicketItems(filenumber)
.ConcaveJobTicketItems = GetConfigConcaveJobTicketItems(filenumber)
FileClose(filenumber)
Catch ex As Exception
ErrorFlag.NumErrors = ErrorFlag.NumErrors + 1
ReDim Preserve ErrorFlag.ErrorDef(ErrorFlag.NumErrors - 1)
With ErrorFlag.ErrorDef(ErrorFlag.NumErrors - 1)
.Number = ErrorFlag.NumErrors - 1
.Description = "Open Config job ticket File Error: " & StatusText + ex.Message
End With
FileClose(filenumber)
End Try
On debugging , I found out that when the cursor hits this statement .ConcaveJobTicketItems , it jumps to the catch block .
The function GetConfigConcaveJobTicketItems(filenumber) where I stepped into has other function calls inside it .
Public Function GetConfigConcaveJobTicketItems(ByRef InFileNumber As Short) As JobTicketConcaveDesignItemsType
With GetConfigConcaveJobTicketItems
.ComfortConic = GetConfigConcaveSphereToricJobTicket(InFileNumber, "ConfortConic")
.Multicurve = GetConfigConcaveSphereToricJobTicket(InFileNumber, "Multicurve")
End With
End Function
When the debug cursor Hits the statement .ComfortConic = GetConfigConcaveSphereToricJobTicket(InFileNumber, "ConfortConic"), I step into the function and see that everything is fine and the cursor moves to the next line.
.Multicurve = GetConfigConcaveSphereToricJobTicket(InFileNumber, "Multicurve")
The GetConfigConcaveSphereToricJobTicket() is defined as
Public Function GetConfigConcaveSphereToricJobTicket(ByRef InFileNumber As Short, ByRef InString As String) As JobTicketSphereToricConcaveItemsType
With GetConfigConcaveSphereToricJobTicket
.Sphere = GetConfigConcaveDesignJobTicket(InFileNumber, InString & "Sphere")
.Toric = GetConfigConcaveDesignJobTicket(InFileNumber, InString & "Toric")
End With
End Function