To activate the track changes in a workbook select (Tools > Track Changes > Highlight Changes).
Any changes made before switching this feature on will not be tracked.
Using this method though will allow the users to remove (or modify) the tracked changes.
If you want to prevent users from removing the tracked changes you must add a password before the workbook is shared.
Please refer to the Protecting the Change History page.
Switching the track changes on
Before using track changes you must define the changes which you want to track.
Select the "Track Changes while editing" checkbox.
The default is to track "All" the changes made by "Everyone" although this dialog box is a little confusing.
Make sure you have the "When" checkbox ticked and "All" is selected.
Make sure you have the "Who" checkbox selected and "Everyone" is selected.
Highlight which changes - Defines exactly what changes to track: when, who and where.
Highlight changes on screen - Indicates any changes as soon as they are made with a cell border and a cell comment.
List changes on a new sheet - All the changes can be inserted on a separate worksheet which is inserted after the last worksheet in the workbook. This is disabled initially because there are no changes to display initially.
Remove the tick from the "Highlight changes on screen" checkbox.
Press OK to enable the tracked changes made from this point forward.
The change history will be kept for 30 days by default. This is to limit the size of the workbook.
The workbook will now be saved as a shared workbook.
You will notice that the title bar for the workbook now has [Shared] appended to the workbook name.
You can control which changes you want to highlight.
Since I last saved - Only the changes since the workbook was last saved;
All - Displays all the changes since the workbook was first saved as a shared workbook;
Not yet reviewed - Only the changes that you have not reviewed;
Since Date - Only the changes since a particular date. Click "since date" and then type in the earliest date you want to view the changes from. The date format must be day, month, year separated with either a dash or a forward slash. It is possible to include a time after the date by using a space to separate the two.
Everyone but me - This allows you to track any changes made by other people.
Allows you to choose a particular range of cells you want to track the changes for as opposed to tracking the whole workbook.
You can drag to select the cells directly while the dialog box is still open.
If a range of cells is specified then Excel will only track the changes within that range.
If this is left blank then the whole workbook will be reviewed.
You can increase or decrease the number of days to keep.
If you are keeping 30 days of tracked changes and you open the workbook for the first time after 2 months you will be able to see all the changes in the last 2 months. When you save the workbook the history from 31 to 60 days will be permanently removed.