Does Onno run in Fritz / Shredder / Aquarium?

Yes. Onno runs in any UCI compatible GUI.

Installation of Onno in Fritz and Shredder has been tested successfully as well as in Arena and SCID.

Why can't I get Onno running (in Fritz / Shredder / Aquarium / SCID / Arena / other GUI)?

The most common causes are:

For further error tracking, please run Onno without a GUI. You can do this by double clicking on deep-onno-1-2-70-w32.exe (or similar according to actual version). You should get a console-like window (most likely black). Type uci in this window and press enter. You might help yourself reading the error messages. If you still don't see what the problem is please include the output in your support request, especially the lines after copyprotection checking.

Can Onno use more then one CPU?

There is a single processor version (Onno) and a multi processor version (Deep Onno). Only the latter can use more then one CPU. See Buy for details.

I didn't get my license / download link.

You receive the download link in two different ways: at the end of the ordering process in your browser and by email.

You receive your license file in three different ways: at the end of the ordering process in your browser, as download link by email and as attachment by email.

So if one way fails there should be a second chance. If you did not receive an email, please check your spam filter. There is only one email containing both download links and the attachment.

I didn't get the newsletter with information about / download link for the update.

Updates can now be found at the download page.

After several attempts to get the newsletter system of share-it working properly, I decided to give up now. I will not send more newsletters for some time. I no longer check or add users manually. My medium-term plan is to set up my own newsletter system.

I don't have a password for the download area.

If you bought Onno at share-it, all information you need is on the download page. Please read it!

I cannot download from the download area.

The most common causes are:

What are (endgame) tablebases?

Tablebases are databases of all positions up to a certain number of men. 5-men-tablebases (7,5 GB) are common, 6-men-tablebases (1,2 TB) are also available.

Tablebases contain the definitive truth on all contained positions, allowing an engine to play perfectly in these positions.

You can buy 5-men-tablebases at any well arranged chess retailer on DVD. Few retailers also offer 6-men, one of them is Steinwender EDV. Usually you will buy 6-men together with 1-2 harddisks which contain them. It is also possible to download the tablebases free of charge and legally from the WWW or by eMule. Further information can be found at https://www.kirill-kryukov.com/chess/tablebases-online/.

Another great site on tablebases is Horizon Chess.

Onno supports tablebases from version 1-1-0 on, namely all 3-, 4-, 5-men and all useful 6-men (i.e. all except 5 vs. 1).