This should do it...
Sub Tester()
Const SERVER_PATH As String = "Y:\QA\Signatures\"
Dim usr As String, fPath As String
usr = Environ("username")
fPath = SERVER_PATH & usr & ".png"
If Dir(fPath, vbNormal) = "" Then
MsgBox "Signature file for '" & usr & "' not found!"
Exit Sub
End If
InsertPicFile fPath, Sheets("Inspectiontype").Range("H19")
'...do other inserts
End Sub
Sub InsertPicFile(sigPath As String, rng As Range)
With rng.Parent.Pictures.Insert(sigPath)
.Left = rng.Cells(1).Left
.Top = rng.Cells(1).Top
End With
End Sub