Restricting Excel sheet to open only within organization network

Question

I want to restrict Excel sheet to open only within my organization's network. If my system is connected with company's internet, only then it should get open. If the system is not connected to internet or connected with outside network, it should not get open.

I am using Macro for this. I have used the below code so far, found this on another answer on Stack Overflow. This code is giving same value for a system in different connected network. This will work only if the system is different. but not for different networks.

Option Explicit

Enum COMPUTER_NAME_FORMAT
    ComputerNameNetBIOS
    ComputerNameDnsHostname
    ComputerNameDnsDomain
     ComputerNameDnsFullyQualified
    ComputerNamePhysicalNetBIOS
    ComputerNamePhysicalDnsHostname
    ComputerNamePhysicalDnsDomain
    ComputerNamePhysicalDnsFullyQualified
End Enum

Declare Function GetComputerNameEx Lib "kernel32" Alias "GetComputerNameExA" 
( _
    ByVal NameType As COMPUTER_NAME_FORMAT, _
    ByVal lpBuffer As String, _
    ByRef lpnSize As Long) As Long

Sub test()
    Dim buffer As String
    Dim size As Long
    size = 255
    buffer = Space(size)
    GetComputerNameEx ComputerNameDnsFullyQualified, buffer, size
    Debug.Print Left$(buffer, size)
End Sub

Answer 1

_{I'll respond even though there was no actual question in your post, and it will probably get closed unless you edit it to add information about a specific programming-related issue, along with examples, detail of what you've tried, and an actual question. (See this and this and this.)}

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The short answer is:

IT'S NOT POSSIBLE.

Anyone who really wants to access your workbook (or any other Office document) can do a quick Google Search to bypass any security "features" you add.

AUTO_OPEN macros and On Open events can be easily bypassed by holding Shift while opening, or distrusting macros in their Trust Centre. (Here is the first result of a Google search on the topic.)

Passwords can be cracked within minutes using freeware utilities or manually with only a few steps. (See my answer here.)

If the people you are concerned about are not computer-savvy, I suppose you could have the workbook silently notify you of where it's being opened (for example, the IP address or computer name)) but, once again, these could be faked or bypassed altogether.

Assuming the issue is concerns over employees using the workbook (or the data it contains) for "unapproved purposes", the ideal solution would be to either start trusting your staff, or if that's not possible, you need to fire them and find people you do trust.

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Edit: Bypassing Workbook_Open

Here's an example of a workbook with a Workbook_Open event, first opened normally, then bypassed by opening the workbook a slightly different way:

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Edit: Prevent Any Code From Running

As a developer, I often keep my macro security settings reduced or off. However, a default installation has security turned on, and even if it was disabled, it's not hard to re-enable security in:

• File ➡Options ➡Trust Centre

You can't force code to run or bypass security programmatically.

Anything you think you can do or find or do to force code to execute without the user's consent will not work, and at the very least will have a workaround.

Why?

Compare it to Virus Scanner software.

Imagine what would happen if code was able to disable your Virus Scanner? That would make all Virus Scanners absolutely useless, forever. If it were possible, virus creators would be doing it routinely.

The same goes for VBA Macro security options: If it could be bypassed programmatically, the "options" wouldn't have any point and wouldn't even be included. It's not a matter of convenience; it's a matter of security.