I am using Tridion R 5.3. I am getting exception while doing undo checkout of a component. It is always showing message "The title is not unique". Exception message is as below:

```
Unable to Undo Check-out Component (tcm:7-122991). The title is not unique.  Error Code: 0x8004026D (-2147220883)  Call stack: VersioningCommon.UndoCheckoutItem ComponentBL.UndoCheckOut Component.UndoCheckOut

```

Can anyone suggest me the root cause. I have check event viewer, but there is no more information. I can do checkin, but I can't do any change in that component.