Hello,
sorry I have only the German Error message for you !

My system:
Joomla 1.5.15
Simple Image Gallery pro 2.0.4
My Site: msprivat.net

I have read the description and have as done everything as have bragged !
But if you click to "Fotoalbum" you get this error:
"Es ist nicht erlaubt diese Ressource einzusehen!"
"It is to be seen not permissibly this resource" (translate with Abacho ...)

What can I do  ???

Are all your site pages accessibles? It looks like you have forbiddern access.
Try to put the gallery to another page.

Hello,
thanks for answer !!
OK, i have my pics in the folder /images/family

the root folder for image gallery are: images
in the site i write: ... {gallery}family{/gallery}

hope that's correct !?
This folder have full access.

What I am saying is that you probably must to login in order to see the page with the gallery.
As I told you before put {gallery}family{/gallery} to another article of your site to see if you may see it.

Hoi Katia,
you were right, if I login, the mistake disappears. Thank you  :)
But now I get the message: "Nothing to see here! ;-)"
the folder "family" was changed to "pictures" ...
I try some more too, but the result was the same !?

If the folder "family" was changed to "pictures" write
{gallery}pictures{/gallery}

However I cannot see SIG PRO in your site...