Are you using Shell or ShellEx?

The path to Adobe has spaces in it, have you double quoted the path string?

What error do you get when you try an open the document?

Hi Alex,

Thanks for your help.

I'm using "Shell" as per Richard Rost's video. I'm very new to VB coding but it's been a while working with access. Yes, I have double quoted the path string too. it is sampling doing nothing.

If Right(Attachments, 4) = ".PDF" Then
    Shell """C:\Program Files (x86)\Adobe\Acrobat Reader DC\Reader\AcroRd32.exe"" """ & Attachments & """", vbNormalFocus
End If

I don't know where I am making mistake.

Can you create a variable and set that to the pat

var file = """C:\Program Files (x86)\Adobe\Acrobat Reader DC\Reader\AcroRd32.exe"" """ & Attachments & """"
MsgBox file
Or
Debug.Print file

Can update your code to use that instead,
Shell file, vbNormalFocus

Then share what is returned.

Use ShellEx. It's easier. I only really show Shell in that seminar to give you an appreciation for ShellEx and why it's so powerful.