Hi Graham,  I have managed to stop the looping but now can get the message to
appear? I tried posting you code in many of the events on control
'Hyperlink1' and even tried adding to the command button 28 again no luck.  
If I click on the cmdPrint button it gives the error 3314 as the required
table field is set to Yes, other than that I cannot get any error message to
appear regarding Hyperlink1, any thoughts.  I have included below the coding
used on the form in the hope that it helps. I have noticed that when I use
tab to move throught the fields it always and only misses out the Hyperlink1
field, is this what is affecting the error coding.  Many thanks for sticking
with this.
Regards, Sue

Option Compare Database

Dim bWasNewRecord As Boolean

Private Sub Combo18_AfterUpdate()
   ' Find the record that matches the control.
   Dim rs As Object

   Set rs = Me.Recordset.Clone
   rs.FindFirst "RegisterNumber = " & Str(Nz(Me![Combo18], 0))
   If Not rs.EOF Then Me.Bookmark = rs.Bookmark
End Sub

Private Sub Combo25_AfterUpdate()

   ' Find the record that matches the control.
   Dim rs As Object

   Set rs = Me.Recordset.Clone
   rs.FindFirst "[IDNo] = " & Str(Nz(Me![Combo25], 0))
   If Not rs.EOF Then Me.Bookmark = rs.Bookmark
End Sub

Private Sub cmdPrint_Click()

   Dim StrWhere As String

  If Me.Dirty Then    'Save any edits.
    Me.Dirty = False
   End If

   If Me.NewRecord Then 'Check there is a record to print
       MsgBox "Select a record to print"

   Else
       StrWhere = "[RegisterNumber] = """ & Me.[RegisterNumber] & """"
       DoCmd.OpenReport "EditFormRpt", acViewPreview, , StrWhere
   End If
   
    End Sub


Private Sub Combo29_AfterUpdate()

   ' Find the record that matches the control.
   Dim rs As Object

   Set rs = Me.Recordset.Clone
   rs.FindFirst "[IDNo] = " & Str(Nz(Me![Combo29], 0))
   If Not rs.EOF Then Me.Bookmark = rs.Bookmark
End Sub

Private Sub Command28_Click()
     
   If IsNull(Me.[Reason(s)forEdit]) And Not IsNull(Me.[RegisterNumber]) Then
       MsgBox "REASONS FOR EDITING MUST BE COMPLETED BEFORE SAVING IS
PERMITTED"
       Cancel = True  'wont let the user continue
       Me.[Reason(s)forEdit].SetFocus
   End If
   
'I always like to trim the value too:
   If Len("" & Trim(Me.ForwardedTo)) = 0 Then
       'The field is empty????????
   End If

End Sub

Private Sub CompanyName_s__BeforeUpdate(Cancel As Integer)
If IsNull(Me.[CompanyName(s)]) And Not IsNull(Me.[RegisterNumber]) Then
  MsgBox "COMPANY NAME DETAILS MUST BE COMPLETED BEFORE SAVING IS PERMITTED"
  Cancel = True  'wont let the user continue
End If
End Sub

Private Sub Subject_BeforeUpdate(Cancel As Integer)
  If IsNull(Me.[Subject]) And Not IsNull(Me.[RegisterNumber]) Then
  MsgBox "SUBJECT DETAILS MUST BE COMPLETED BEFORE SAVING IS PERMITTED"
  Cancel = True  'wont let the user continue
End If
End Sub

Private Sub ForwardedTo_BeforeUpdate(Cancel As Integer)
  If IsNull(Me.[ForwardedTo]) And Not IsNull(Me.[RegisterNumber]) Then
  MsgBox "FORWARDED TO DETAILS MUST BE COMPLETED BEFORE SAVING IS PERMITTED"
  Cancel = True  'wont let the user continue
End If
End Sub

Private Sub ReceivedFrom_BeforeUpdate(Cancel As Integer)
  If IsNull(Me.[ReceivedFrom]) And Not IsNull(Me.[RegisterNumber]) Then
  MsgBox "RECEIVED FROM DETAILS MUST BE COMPLETED BEFORE SAVING IS PERMITTED"
  Cancel = True  'wont let the user continue
End If
End Sub

Private Sub Form_AfterDelConfirm(Status As Integer)
Call AuditDelEnd("audTmpHYInReg", "audHYInReg", Status)
End Sub

Private Sub Form_AfterUpdate()
Call AuditEditEnd("HYInReg", "audTmpHYInReg", "audHYInReg", "IDNo",
Nz(Me!IDNo, 0), bWasNewRecord)
End Sub

Private Sub Form_BeforeUpdate(Cancel As Integer)
 
   UpdateLog = CurrentUser() & " " & Now()
   bWasNewRecord = Me.NewRecord
   Call AuditEditBegin("HYInReg", "audTmpHYInReg", "IDNo", Nz(Me.IDNo, 0),
bWasNewRecord)
   
End Sub
   
Private Sub Form_Delete(Cancel As Integer)
Call AuditDelBegin("HYInReg", "audTmpHYInReg", "IDNo", Nz(Me.IDNo, 0))
End Sub

Private Sub Form_Load()
DoCmd.Maximize
End Sub

Private Sub Command32_Click()
On Error GoTo Err_Command32_Click

   Dim stDocName As String
   Dim stLinkCriteria As String

   stDocName = "RegEditForm"
   DoCmd.OpenForm stDocName, , , stLinkCriteria

Exit_Command32_Click:
   Exit Sub

Err_Command32_Click:
   MsgBox Err.Description
   Resume Exit_Command32_Click
   
End Sub

Private Sub Command33_Click()
On Error GoTo Err_Command33_Click

   Dim stDocName As String
   Dim stLinkCriteria As String

   stDocName = "RegEntryForm"
   DoCmd.OpenForm stDocName, , , stLinkCriteria

Exit_Command33_Click:
   Exit Sub

Err_Command33_Click:
   MsgBox Err.Description
   Resume Exit_Command33_Click
   
End Sub