Here's some code I found to check for invalid reg apps.
You should be able to this modify to your needs...
[code]
'Verify registered apps when drawing loads
Private Sub VerifyRegistered_Apps()
Dim oRegApp As AcadRegisteredApplication
Dim oRegApps As AcadRegisteredApplications
Dim colBadApps As Collection
Dim strMSG As String
Dim i As Integer
'get the current collection of registered apps
Set oRegApps = ThisDrawing.RegisteredApplications
' start a new collection for bad apps
Set colBadApps = New Collection
' review each registered application
For Each oRegApp In oRegApps
'Debug.Print oRegApp.Name
' if there's a "*" in the name, damn good chance it's BAD!
If InStr(1, oRegApp.Name, "*") > 0 Then
colBadApps.Add oRegApp.Name
End If
Next
' if we found some bad apps, report them!
If colBadApps.Count > 0 Then
'build list of bad ones
For i = 1 To colBadApps.Count
strMSG = strMSG & colBadApps.Item(i) & vbNewLine
Next
'display the bad news
MsgBox "There's a good chance this drawing has corruputed data!" & vbNewLine & _
"INVALID REGISTERED APPS FOUND!" & vbNewLine & _
strMSG
End If
Set colBadApps = Nothing
Set oRegApp = Nothing
Set oRegApps = Nothing
End Sub
[/code]
