"uninstallation procedure ignores if installed files are in use"

[tindu]

i am getting a problem during the uninstallation(MSI) if the installed
exe file are in use that means this file is locked.it simply ignores
the files rather than showing a dialog box message during
uninstallation procedure.it happens only with the exe file of less
size.i am not getting the thing why it is showing this type of
behaviour.plz suggest...