This method will introduce a VBA to count the hours or minutes spent on the specified appointment or meeting in Outlook. Please do as follows:

1. Shift to the Calendar folder, and click to select the appointment or meeting which you will count spent hours.

2. Press Alt + F11 keys simultaneously to open the Microsoft Visual Basic for Applications window.

3. Click Insert > Module, and then paste below VBA code into the opening Module window.

VBA: Count hours/minutes spent on an appointment or meeting in Outlook

Sub CountTimeSpent()
Dim oOLApp As Outlook.Application
Dim oSelection As Outlook.Selection
Dim oItem As Object
Dim iDuration As Long
Dim iTotalWork As Long
Dim iMileage As Long
Dim iResult As Integer
Dim bShowiMileage As Boolean

bShowiMileage = False

iDuration = 0
iTotalWork = 0
iMileage = 0

On Error Resume Next

    Set oOLApp = CreateObject("Outlook.Application")
Set oSelection = oOLApp.ActiveExplorer.Selection

    For Each oItem In oSelection
If oItem.Class = olAppointment Then
iDuration = iDuration + oItem.Duration
iMileage = iMileage + oItem.Mileage
ElseIf oItem.Class = olTask Then
iDuration = iDuration + oItem.ActualWork
iTotalWork = iTotalWork + oItem.TotalWork
iMileage = iMileage + oItem.Mileage
ElseIf oItem.Class = Outlook.olJournal Then
iDuration = iDuration + oItem.Duration
iMileage = iMileage + oItem.Mileage
Else
iResult = MsgBox("Please select some Calendar, Task or Journal items at first!", vbCritical, "Items Time Spent")
Exit Sub
End If
Next

Dim MsgBoxText As String
MsgBoxText = "Total time spent: " & vbNewLine & iDuration & " minutes"

If iDuration > 60 Then
MsgBoxText = MsgBoxText & HoursMsg(iDuration)
End If

If iTotalWork > 0 Then
MsgBoxText = MsgBoxText & vbNewLine & vbNewLine & "Total work recorded; " & vbNewLine & iTotalWork & " minutes"

If iTotalWork > 60 Then
MsgBoxText = MsgBoxText & HoursMsg(iTotalWork)
End If
End If

If bShowiMileage = True Then
MsgBoxText = MsgBoxText & vbNewLine & vbNewLine & "Total iMileage; " & iMileage
End If

    iResult = MsgBox(MsgBoxText, vbInformation, "Items Time spent")

ExitSub:
Set oItem = Nothing
Set oSelection = Nothing
Set oOLApp = Nothing
End Sub

Function HoursMsg(TotalMinutes As Long) As String
Dim iHours As Long
Dim iMinutes As Long
iHours = TotalMinutes \ 60
iMinutes = TotalMinutes Mod 60
HoursMsg = " (" & iHours & " Hours and " & iMinutes & " Minutes)"
End Function

4. Press the F5 key or click the Run button to run this VBA.

And now a dialog box pops out and shows how many hours/minutes the selected appointment/meeting spent. See screenshot:

Note: You can select multiple appointments or meetings at the same time to count total hours/minutes spent on them with this VBA code.

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