Originally Posted by linuxgeek82
just reinstall it if you're worried about.
apt-get reinstall aptitude
you didn't hurt your system as this is not a system dependent application.
I have some doubts that this would do the trick.
That /root/.aptitude file is simply the user land config file for aptitude for the user root. If the OP is not using aptitude there is no problem.
If the OP used aptitude once that file should be recreated at that time.
Seeing that it was deleted the OP was logged in a root at the time. If logging in as root is common then that file should also regenerate when logging in as root.
This is a good example of why logging in as root is not encouraged. It is too easy to remove things that should be left alone. There is no damage done in this case but deleting files just because you don't know what they are for is not the way to find out.