Here is a quick and simple problem.
If I type The command './kaid2' works fine. If I type I end up with an error, the command 'kaid' now says command not found, and

it's

ln -s <target> <symbol>

not

ln -s <symbol> <target>

In other words, in your second example, you make a symbolic link called /usr/bin/kaid that links to something called "kaid" which would likely be in ./ and not really be anything. You should do:

ln -s /usr/bin/kaid kaid

Nope, you're backwards.

From man ln:
ln [OPTION]... [-T] TARGET LINK_NAME (1st form)
ln [OPTION]... TARGET (2nd form)
ln [OPTION]... TARGET... DIRECTORY (3rd form)
ln [OPTION]... -t DIRECTORY TARGET... (4th form)

You make a link to a target---the target name always comes first---except #4 (which I do not understand)

In OPs 1st example, the order was target, link and the link worked

I think the problem has to do with using full pathnames in certain situations, but lets confirm with OP---where in fact is the target file? Is it possible that the first example worked because kaid2 is really the target?

Could you check if your right the next time you post? Its not that hard. I bet you $999999999999 you have this program (ln) too and are capable of checking yourself.

timrs;
Who is this addressed to? I suddenly find that I don't know what this thread is about. You posed a question--- Do you now have the answer?

If your post is saying that someone made a mistake, perhaps you should say what the mistake was......

No, sorry, but the command i have is correct... it works in the current directory, but when the link is in /usr/bin it doesn't work

As I said in my other post, it has to do with specifying full path names. I just tried a few experiments.
If I link OUT of a folder, I needed to specify the full path name.
When in /opt:
ln -s vpnclient /home/mherring/Desktop does not work
whereas
ln -s /opt/vpnclient /home/mherring/Desktop DOES work

But if I am in /home/mherring/Desktop, I can do:
ln -s /opt/vpnclient vpnclient, and it works

And that's the truth........

Thankyou, this is strange though -- did the developers do this on purpose?

As opposed to what? accident? mistake?

No, I think there is probably a rational reason for it to be that way--but I have never seen it...

The really easy way to stay out of trouble is to always link IN, using the default link name:
ln -s /path/path/target
Automatically creates the link in the current directory with the name of "target"

I think its because when ln -s 1 /dir/2 is made, the file /dir/2 is literally linked to 1, and there is no 1 in the directory 2 is in -- thats the best I can explain it