error 404 displaying singles articles from main menu

Hello, Ineed help to fix a problem, cause I have no clue how to do it.
I used the quickstart installation, and in the very first time the articles showns perfectly.
BUT, now only the items from the menu that directs to single articles are not working.
Imediatly redirect to index.php?error=404&itemId=99999
If I type in the correct url to see an article, also happens the same 404 error.

can you help me?

the website is: http://loudinitaxi.com/
"Servicios" and "Tours por Barcelona" items are good examples of the problem.

thanx a lot!

Hi

Can You please tell me how are You menu items for this broken links constructed ? Are You using a single article type or an external url ? Are You using any SEF 3rd party extensions ?

Hi

Can You please tell me how are You menu items for this broken links constructed ? Are You using a single article type or an external url ? Are You using any SEF 3rd party extensions ?

Hello, Iam using single article type.. the most simple way to use it, (no SEF 3rd party)
and if I try to create another one with the single articles, it happen the same, not working..
really extrange.. ((

Hi

Have You found a solution ? I'm checking "Servicios" and "Tours por Barcelona" menu links right now and there is no error any more. If yes than please let me know what was the problem in case someone else will be looking for solution to similar problem.

If it's still not solved than please send me an access to joomla panel and point where the problem can still be visible.