First, a moderator's note: I have merged that second thread into this one...

Dolly, I have never heard of a .CPR file before either in the root directory or elsewhere. This is the problem with your line of questioning. You have put so much stuff into the root filesystem that you now have problems. And we don't know how to help you. I would hope the only the root user can put files in /. It must have been you or someone else with the root password who created that file.

Ideally, the root filesystem should not be changing very much. It should be os stuff only. There are a few text files in /etc and so on that will be updated as the system is used. But these should be small and the size of root should not change very much. Putting /usr under the root filesystem is ok, it too should be os stuff and should not change very much. But putting /var there is a massive problem. Users can create files under /var. That's why /var really should have been separate. I see that Solaris 8 is doing this by default. Still I don't think it's a good idea.

Mu guess is that most of your problem will be under /var, and I would start there. But whoever created a file /.CPR could be dumping files anywhere else under root. Cleaning this up could be a lot of work. Rather than trim .CPR, I would move it.

Log files, and wtmpx is one, will grow until you trim them. Since you're in a crisis, I would just
"cp /dev/null wtmpx" for now.

Here is one thing that I do to find where my space went...
cd /var
du -sk * | sort -n

The lines with the big numbers are where to look first. In your case, it looks like /var/run is a separate filesystem, so ignore that one for now.

And this was only an example... I might next do
cd /var/spool
du -sk * | sort -n
as I track this down.

Also, you give a limited list of files rather than * when you run the du.