Force connections to a remote drive

**Michel Posseth [MCP]** · Oct 24 '08, 09:35 PM

Re: Force connections to a remote drive

This looks more like a SAMBA misconfiguratio n to me , just a thought is
netbios enabled on the Windows computers ?
as i remember simular issues in the company i previously worked for . it
turned out that the Windows XP machines had standard netbios dissabled
enabling netbios solved these issues .

regards

Michel

<vbshanes@gmail .comschreef in bericht
news:9c14f597-5735-4d34-9dfa-c89781eb123d@t1 8g2000prt.googl egroups.com...

We use Samba on a SCO Unix box as our file server / backup device. I
have a directory mapped as a Windows drive. I read / write files from
this remote drive with my VB,net application. This arrangement works
99.99% of the time.
>
That being said, Windows does not automatically connect to the remote
drive at system boot every once in a great while. Some of our
customers have certain Windows boxes that the problem is a bit more
frequent.
>
The easy work around is to go into Windows Explorer and double click
on the remote drive. Every program in Windows can now see the drive.
That's not very professional.
>
I want to force my application to do the same sort of connection that
Windows Explorer is doing. Any ideas?
>
Thanks.

**Bob Altman** · Oct 25 '08, 12:35 AM

Re: Force connections to a remote drive

<vbshanes@gmail .comwrote in message
news:9c14f597-5735-4d34-9dfa-c89781eb123d@t1 8g2000prt.googl egroups.com...

We use Samba on a SCO Unix box as our file server / backup device. I
have a directory mapped as a Windows drive. I read / write files from
this remote drive with my VB,net application. This arrangement works
99.99% of the time.
>
That being said, Windows does not automatically connect to the remote
drive at system boot every once in a great while. Some of our
customers have certain Windows boxes that the problem is a bit more
frequent.
>
The easy work around is to go into Windows Explorer and double click
on the remote drive. Every program in Windows can now see the drive.
That's not very professional.
>
I want to force my application to do the same sort of connection that
Windows Explorer is doing. Any ideas?

You can try accessing a file or a folder on the drive from code. That might
do whatever magic Windows does when you double-click drive letter. If that
doesn't work then you can look at the WNetAddConnecti on2 and
WNetCancelConne ction2 APIs, which will let you mount and dismount network
files programmaticall y.

**Brian** · Oct 26 '08, 03:45 AM

Re: Force connections to a remote drive

What verson of Samba are you using? What verison of SCO Unix?
I had this problem a few years ago, well it was more like Samba on FlexOS,
but the problem was only intermit.

<vbshanes@gmail .comwrote in message
news:9c14f597-5735-4d34-9dfa-c89781eb123d@t1 8g2000prt.googl egroups.com...

We use Samba on a SCO Unix box as our file server / backup device. I
have a directory mapped as a Windows drive. I read / write files from
this remote drive with my VB,net application. This arrangement works
99.99% of the time.
>
That being said, Windows does not automatically connect to the remote
drive at system boot every once in a great while. Some of our
customers have certain Windows boxes that the problem is a bit more
frequent.
>
The easy work around is to go into Windows Explorer and double click
on the remote drive. Every program in Windows can now see the drive.
That's not very professional.
>
I want to force my application to do the same sort of connection that
Windows Explorer is doing. Any ideas?
>
Thanks.

**vbshanes@gmail.com** · Oct 30 '08, 03:55 PM

VB,Net Class (2005) to handle the connections

Appologies to word wrapping.

There is more code than the bare minimum to get the class to work. I
put an error routine to get the english meaning of the returned error
codes. Also, all of the constants defined by the Microsoft MSDN2 pages
are defined, although I only needed a couple of them.

Enjoy

Imports System.Runtime. InteropServices
Public Class clsConnectDrive
Private Declare Function WNetAddConnecti on2 Lib "mpr.dll" Alias _
"WNetAddConnect ion2A" (ByVal netResource As NETRESOURCE, _
ByVal password As [String], ByVal Username As [String], _
ByVal Flag As Integer) As Integer

Private Declare Function WNetCancelConne ction2 Lib "mpr.dll" Alias
_
"WNetCancelConn ection2A" (ByVal lpName As String, _
ByVal Flag As Integer, ByVal fForce As Integer) As Integer

Private m_strDrive As String
Private m_strNetworkSha re As String
Private m_intError As Integer

<StructLayout(L ayoutKind.Seque ntial)_
Class NETRESOURCE
Public dwScope As Integer
Public dwType As Integer
Public dwDisplayType As Integer
Public dwUsage As Integer
Public LocalName As String
Public RemoteName As String
Public Comment As String
Public Provider As String
End Class

'---------- Network Constants ----------
Private Const NO_ERROR As Integer = 0
Private Const CONNECT_UPDATE_ PROFILE As Integer = &H1 '
Disconnect

Private Const RESOURCETYPE_AN Y As Integer = &H0
Private Const RESOURCETYPE_DI SK As Integer = &H1
Private Const RESOURCETYPE_PR INT As Integer = &H2

Private Const RESOURCE_CONNEC TED As Integer = &H1
Private Const RESOURCE_GLOBAL NET As Integer = &H2
Private Const RESOURCE_REMEMB ERED As Integer = &H3

Private Const RESOURCEDISPLAY TYPE_GENERIC As Integer = &H0
Private Const RESOURCEDISPLAY TYPE_DOMAIN As Integer = &H1
Private Const RESOURCEDISPLAY TYPE_SERVER As Integer = &H2
Private Const RESOURCEDISPLAY TYPE_SHARE As Integer = &H3

Private Const RESOURCEUSAGE_C ONNECTABLE As Integer = &H1
Private Const RESOURCEUSAGE_C ONTAINER As Integer = &H2

' Error Constants:
Private Const ERROR_ACCESS_DE NIED As Integer = 5&
Private Const ERROR_ALREADY_A SSIGNED As Integer = 85&
Private Const ERROR_BAD_DEV_T YPE As Integer = 66&
Private Const ERROR_BAD_DEVIC E As Integer = 1200&
Private Const ERROR_BAD_NET_N AME As Integer = 67&
Private Const ERROR_BAD_PROFI LE As Integer = 1206&
Private Const ERROR_BAD_PROVI DER As Integer = 1204&
Private Const ERROR_BUSY As Integer = 170&
Private Const ERROR_CANCELLED As Integer = 1223&
Private Const ERROR_CANNOT_OP EN_PROFILE As Integer = 1205&
Private Const ERROR_DEVICE_AL READY_REMEMBERE D As Integer = 1202&
Private Const ERROR_EXTENDED_ ERROR As Integer = 1208&
Private Const ERROR_INVALID_P ASSWORD As Integer = 86&
Private Const ERROR_NO_NET_OR _BAD_PATH As Integer = 1203&

'---------- Start Code ----------
Public Sub New(ByVal Drive As String, ByVal NetworkShare As
String)
m_strDrive = Drive
If m_strDrive.Leng th 1 Then m_strDrive =
m_strDrive.Subs tring(0, 1)
m_strDrive += ":"
m_strNetworkSha re = NetworkShare
End Sub

'---------- Connect a drive ----------
Public Function DriveConnect(Op tional ByVal IgnoreAlreadyCo nnected
As Boolean = True) As Integer
Dim myNetResource As New NETRESOURCE
myNetResource.d wScope = RESOURCE_GLOBAL NET
myNetResource.d wType = RESOURCETYPE_DI SK
myNetResource.d wDisplayType = RESOURCEDISPLAY TYPE_SHARE
myNetResource.d wUsage = RESOURCEUSAGE_C ONNECTABLE
myNetResource.L ocalName = m_strDrive
myNetResource.R emoteName = m_strNetworkSha re
myNetResource.P rovider = Nothing
m_intError = WNetAddConnecti on2(myNetResour ce, Nothing,
Nothing, 0)
If m_intError = ERROR_ALREADY_A SSIGNED AndAlso
IgnoreAlreadyCo nnected Then m_intError = NO_ERROR
Return m_intError
End Function

'---------- Disconnect a drive ----------
Public Function DriveDisconnect () As Integer
m_intError = WNetCancelConne ction2(m_strDri ve,
CONNECT_UPDATE_ PROFILE, 0)
Return m_intError
End Function

'---------- Error Code Description ----------
' Use the last error from either the connect or disconnect
Public Function ErrorCodeMeanin g() As String
Dim m_strMessage As String = "*** Undefined ***"
Select Case m_intError
Case NO_ERROR : m_strMessage = ""
Case ERROR_ACCESS_DE NIED : m_strMessage = "Access Denied"
Case ERROR_ALREADY_A SSIGNED : m_strMessage = "Already
Assigned"
Case ERROR_BAD_DEV_T YPE : m_strMessage = "Bad Device Type"
Case ERROR_BAD_DEVIC E : m_strMessage = "Bad Device"
Case ERROR_BAD_NET_N AME : m_strMessage = "Bad Net Name"
Case ERROR_BAD_PROFI LE : m_strMessage = "Bad Profile"
Case ERROR_BAD_PROVI DER : m_strMessage = "Bad Provider"
Case ERROR_BUSY : m_strMessage = "Busy"
Case ERROR_CANCELLED : m_strMessage = "Cancelled"
Case ERROR_CANNOT_OP EN_PROFILE : m_strMessage = "Can Not
Open Profile"
Case ERROR_DEVICE_AL READY_REMEMBERE D : m_strMessage =
"Device Already Remembered"
Case ERROR_EXTENDED_ ERROR : m_strMessage = "Extended
Error"
Case ERROR_INVALID_P ASSWORD : m_strMessage = "Invalid
Password"
Case ERROR_NO_NET_OR _BAD_PATH : m_strMessage = "No Network
or Bad Path"
Case 53 : m_strMessage = "Can Not Connect - Check Samba
Log"
Case Else : m_strMessage = "*** Undefined ***"
End Select
Return m_strMessage
End Function
End Class