I was trying to checkout a file and it went it to \"Checkout but removed\" state.
I am not able to undocheckout it and have no clue what needs to be done next.
You should be to undo checkout through the GUI:
Even if that file is not visible on the disk, the "Find checkout" GUI will list it as checked out.
Another solution is to copy the file from another view, for instance a dynamic view with the same config spec (easy to create, and providing a quick access to the same file).
If you copy it on your snapshot view, the file will be listed as "checked out" (but with no modifications yet), and you can resume working on it.
The simplest way to resolve this is to just create a new file with the same name. Then file is not missing any more and you can undo checkout and then check out again to start fresh. On the command line:
$ cleartool ls your_file.c
your_file.c: Checkout but removed
your_file.c@@
$ touch your_file.c
$ cleartool ls your_file.c
your_file.c@@/main/branch1/branch2/14 Rule: ...whatever...
$ cleartool unco -nc your_file.c
$ cleartool co -nc your_file.c
Checked out your_file.c
$
I do not have access to clearcase any longer, so the above is just by (old) memory, but you get the idea. If you are not using the command line, just copy any file to your_file.c, undo checkout and then check out.