Communicating data between all users with a database - excel

Question

I'm currently working on a program for my company that will be used to communicate various information between users, among other things that aren't important at the moment. One of the things that is going to be communicated is a daily tasks checklist. Basically, the intent is to have a check list that syncs between all users, so if one user checks off a task, everyone else can see that the task has been completed.
So far what I have done is I have created a DataGrid object to hold the check boxes. The box starts empty, but when the program loads, the following code is run, which populates the list.
Private Sub chkListPop()
If System.IO.File.Exists(chkListPath) Then
Dim newChk As CheckBox
Dim xlApp As Microsoft.Office.Interop.Excel.Application
Dim xlWorkBooks As Microsoft.Office.Interop.Excel.Workbook
Dim xlWorkSheet As Microsoft.Office.Interop.Excel.Worksheet
Dim rng As Microsoft.Office.Interop.Excel.Range
Dim r As Byte
xlApp = New Microsoft.Office.Interop.Excel.Application
xlWorkBooks = xlApp.Workbooks.Open(chkListPath)
xlWorkSheet = xlWorkBooks.Worksheets("Tasks")
rng = xlWorkSheet.Range("A2")
r = 0
Do While rng.Offset(r).Value <> ""
chkListContainer.Items.Add(New Controls.CheckBox)
newChk = chkListContainer.Items.Item(r)
newChk.Content = rng.Offset(r).Value
Try
If rng.Offset(r, 1).Value = True Then
newChk.IsChecked = True
End If
Catch
End Try
r = r + 1
Loop
xlApp.DisplayAlerts = False
xlWorkBooks.Save()
xlWorkBooks.Close()
xlApp.DisplayAlerts = True
xlApp.Quit()
End If
End Sub
Basically, the sub reads an excel file and, for each line in the file, creates a checkbox with the true false value in the second column. I imagine there has to be a more elegant solution to do this. I am not a programmer by training, so I have limited knowledge on topics this "complex". Whats a better way to do this other than using an excel file? Should I use an Access database or and SQL database instead? This code works, but I just feel like its wrong somehow.
Additionally, I am having trouble figuring out how to update the file when someone checks off a task. For now I just have a timer running, and every X minutes, the program updates the excel file. Here's the code for how that works:
Public Sub chkListSendData()
If System.IO.File.Exists(chkListPath) Then
Dim newChk As CheckBox
Dim xlApp As Microsoft.Office.Interop.Excel.Application
Dim xlWorkBooks As Microsoft.Office.Interop.Excel.Workbook
Dim xlWorkSheet As Microsoft.Office.Interop.Excel.Worksheet
Dim rng As Microsoft.Office.Interop.Excel.Range
Dim r As Byte
xlApp = New Microsoft.Office.Interop.Excel.Application
xlWorkBooks = xlApp.Workbooks.Open(chkListPath)
xlWorkSheet = xlWorkBooks.Worksheets("Tasks")
rng = xlWorkSheet.Range("A2")
r = 0
Do While rng.Offset(r).Value <> ""
Try
newChk = chkListContainer.Items.Item(r)
Catch
chkListContainer.Items.Add(New Controls.CheckBox)
newChk = chkListContainer.Items.Item(r)
newChk.Content = rng.Offset(r).Value
End Try
If newChk.IsChecked Then
rng.Offset(r, 1).Value = True
End If
r = r + 1
Loop
xlApp.DisplayAlerts = False
xlWorkBooks.Save()
xlWorkBooks.Close()
xlApp.DisplayAlerts = True
xlApp.Quit()
End If
End Sub
Public Sub chkListGetData()
If System.IO.File.Exists(chkListPath) Then
Dim newChk As CheckBox
Dim xlApp As Microsoft.Office.Interop.Excel.Application
Dim xlWorkBooks As Microsoft.Office.Interop.Excel.Workbook
Dim xlWorkSheet As Microsoft.Office.Interop.Excel.Worksheet
Dim rng As Microsoft.Office.Interop.Excel.Range
Dim r As Byte
xlApp = New Microsoft.Office.Interop.Excel.Application
xlWorkBooks = xlApp.Workbooks.Open(chkListPath)
xlWorkSheet = xlWorkBooks.Worksheets("Tasks")
rng = xlWorkSheet.Range("A2")
r = 0
Do While rng.Offset(r).Value <> ""
Try
newChk = chkListContainer.Items.Item(r)
Catch
chkListContainer.Items.Add(New Controls.CheckBox)
newChk = chkListContainer.Items.Item(r)
newChk.Content = rng.Offset(r).Value
End Try
Try
If rng.Offset(r, 1).Value = True Then
newChk.IsChecked = True
End If
Catch
End Try
r = r + 1
Loop
xlApp.DisplayAlerts = False
xlWorkBooks.Close()
xlApp.DisplayAlerts = True
xlApp.Quit()
End If
End Sub
Private Sub chkTimer()
Dim dispatcherTimer As DispatcherTimer = New DispatcherTimer()
AddHandler dispatcherTimer.Tick, AddressOf OnTimedEvent
dispatcherTimer.Interval = New TimeSpan(0, 1, 0)
dispatcherTimer.Start()
End Sub
Private Sub OnTimedEvent(ByVal sender As Object, ByVal e As EventArgs)
chkListGetData()
chkListSendData()
End Sub
In my testing, this has worked fine, but I have a feeling that when lots of people are using the program, this will not work so well when multiple people attempt to update the file at the same time. If I'm wrong and this code is perfect, that's great, but I doubt that is the case. If there's a better way to handle this kind of thing, I would love to learn how to implement it in this program.
Thanks, in advance, for your help.