Edit: then the alternative is to create an 'on-time' macro to replicate clicking the 'Save' button. Try the following method.
Copy the following event handler to the clipboard:
Private Sub Workbook_Open()
CallSave
End Sub
Press ALT + F11
Double click 'This Workbook' in the Microsoft Excel VBA Project properties in the upper left quadrant.
Paste the event handler into the editing area to the right and close the VBE.
Still in the VBE, select INSERT > MODULE in the menu options at the top.
Copy the following two macros to the clipboard:
Sub CallSave()
Application.OnTime Now + TimeValue("00:03:00"), "SaveIt"
End Sub
Sub SaveIt()
Application.DisplayAlerts = False
ActiveWorkbook.Save
CallSave
End Sub
Paste them into the newly created Module.
Close the VBE and return to the worksheet. Save the workbook.
Now, each time the workbook is opened, it will trigger the CallSave macro. After 3 minutes elapse, that macro will call the SaveIt macro which saves the workbook without prompting the user. After saving it calls the CallSave macro again. After 3 more minutes the workbook will be saved again. This loop will repeat as long as the workbook is open.
Change the ("00:03:00") element to whatever timing cycle you wish, i.e. ("00:05:00") would be a 5 minute cycle.
Advise if additional assistance is needed.
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The 'AutoSave' function in Excel 2010 has morphed into the AutoRecover function, located in the File > Options > Save settings.
In those settings you have the ability to set the 'save to' file location. Assuming you are on a server, you should be able to direct the save function to a server drive.
Without the ability to fully test this, I would suggest trying the following WorkBook_Open event handler. Change the timing cycle to whatever you wish. This sets it at 5 minutes.
Copy the following code to the clipboard:
Private Sub Workbook_Open()
With Application.AutoRecover
.Enabled = True
.Time = 5
End With
ActiveWorkbook.EnableAutoRecover = True
End Sub
Press ALT + F11
Double click 'This Workbook' in the Microsoft Excel VBA Project properties in the upper left quadrant.
Paste the event handler into the editing area to the right and close the VBE.
Save the workbook.