JPDutch,

Something like this?
Sub tgr()
    
    Const strFldrPath As String = "H:\SAFETY\FORMS\ 300 & 300A\2011\"
    Dim strFile As String: strFile = Dir(strFldrPath)
    
    While strFile <> vbNullString
        Name strFldrPath & strFile As Replace(strFldrPath & strFile, "2010", "2011")
        strFile = Dir
    Wend
    
End Sub