I have FC-6 and use KDE.

I removed what I thought was a single file. Yum said no other files were dependent on the file. But when I removed it (in Kyum) a lot of other files and applications were removed. It really screwed up my system.

Is there a way to reverse what happened, so I could have it like nothing ever happened?

Thanks,

royeo

I guess you are saying you actually removed packages, rather than single files?

If you know what packages were removed, then you should be able to simply reinstall them, unless the computer no longer starts after they were removed?

Posting what you removed will also aid us in determining how extensive the damage is.

Take a look at the difference between /var/log/rpms1 and /var/log/rpms. The /var/log/rpms is the latest compilation of all rpms installed on the system, rpms1 or similar, is a compilation of all installed packages a week before rpms. Depending on how long you had Fedora, there will/may also be rpms2, rpms3, etc., they should have a date as to when they were made.
Although I've never had the chance to use rpm query, read the man pages for rpm to find how to query the dependencies of the original first package you tried to remove which also removed the dependencies, this is the best route to find what all packages were removed.
Also look at/for a log file in /var possibly called "yum.log" which may also have a record of what was installed/un-installed lately.