I am searching for a way to reset the world in Creatures 1, I ve tried the Emregency kit, but it's not possible to install it, even manually. So, I deleted the directories, but some files are still hidden on the hard drive like it was 15 years ago and there is no way to uninstall this game.
Could you help me?

Reinstall the game first. I'm pretty sure somewhere in the start menu there used to be a second application bundled with the game to reset the world. Don't remember what it was called. If it's not in the start menu, hunt around in the installation directory.
If you can't find it, check the manual.

Yes, you are talking about the Emergency Kit wich was forgotten by GOG in the package.

Uh oh, that's a bit of a flub. The Emergency Kit was quite handy.

I bought C1 the other day, during the sale. It seems the Emergency Kit indeed no longer works. After a bit of flddling, I found that deleting your Creatures 1 directory in My Documents\Creatures will delete the world - running Creatures again will create a fresh one.
I'm not sure what to do about the other missing components of the Emergency Kit, such as restoring the hatchery eggs though.

Reseting the hatchery in no longer possible, which means you have to install the game on another computer to have more eggs.
So, Mr GOG, we need a patch here !

MY health kit wont come up . It keeps popping an error message that says" no error message is available" . I attached a screen shot. please help . Thank You !

It might be best to post a new topic in the future, since this issue isn't related to resetting the world. However, the Health Kit issue should be resolved by running the game as an administrator. You can find a similar discussion here. Good luck, and I hope everything is working again soon!

I've tried this step for step and it still didn't reset my world.. Any idea why? Or any other ideas how to reset?

If you're still stumped on this one, that's because your world is NOT in GOG's folder by default, but in the DOCUMENTS folder.

The World.sfc in your default install location will be the exact same size as Eden.sfc. You can copy that one to the Documents folder containing a bigger World.sfc file and overwrite it, and it'll have the same effect as copying and renaming Eden.sfc.

(To know you're in the right folder, look on the Genetics sub folder. If it only has the mum and dad .gen files, it's the default install. If it has moniker (four-character files unique to each norn) .gen files, that's the folder the game stores its changes to the base game in.)

As for using Backup.exe (the Emergency Kit), it DOES try to reset the world... by generating World.sfc in the folder it's in rather than the one the game saves to on a split install, oops. The Hatchery could only be restocked when empty, but GOG's version automatically replenishes it once there's no eggs left. It DOES restock the Health and Science Kits, though.