Hi David, thanks for trying help me, I really hope we can solve it, because in two days I have to be online!
The problem is that I want to show category blog and it shows category default, even if my configuration is setted in order to prevent it and to prevent duplication url.
The other problem, maybe linked to this first one, is that it duplicated ulr category default and it uses this url default instead of the url blog.
I also changed it manually, but it duplicates url and automatically substitute it. Results is that I can see category blog only for few time, after that it returns to category default.
I also purge url, after changing settings, and cleaning cache, but the problem is always on my site.
The only one thing I never did is updating url.
Maybe my configuration is wrong, in order to really understand it, I write my BASIC and ADVANCED configuration settings, CACHE configuration and CONTENT extension management configuration.
BASIC Configuration
Tooltip JoomSEF Enabled? Si
Tooltip Disable creation of new SEF URLs? No
Tooltip Number duplicate URLs? No
Tooltip All lowercase? Si
Tooltip Use index for sections and categories Si
ADVANCED configuration
Exclude source info (Itemid) No
Tooltip Reappend source (Itemid) Si
Tooltip Ignore multiple sources (Itemids) Si
Tooltip Append non-SEF variables to URL Si
Tooltip Be tolerant to trailing slash? Si
Tooltip Redirect nonSEF URLs to SEF? Si
Tooltip Use Moved Permanently redirection table? Si
Tooltip Ask before saving URL to Moved Permanently table? Si
Tooltip Do not remove SID from SEF URL? No
Tooltip Set server QUERY_STRING? Si
Tooltip Parse Joomla SEO links? Si
Tooltip Filter variable values? Si
Tooltip Filter system variables: Si
Tooltip Prevent non-SEF variables from overwriting the parsed ones: Si
Tooltip Automatic canonical link generation: Si
Tooltip SEF URLs using component template: No
Tooltip Set page base href value: yes always use base url
Tooltip Fix index.php links: Si
Tooltip Fix document format: No
Enable URL source tracing? No
CACHE config
Use cache? Si
Tooltip Maximum cache size: 1000
Tooltip Minimum cache hits count: 10
Tooltip Record hits for cached URLs: Si
Tooltip Display error if cache gets corrupted: No
CONTENT extension mgmt
Handle pagination as non-SEF No
Guess Itemid No
Compatibility mode No
URL Settings
Show Category Si
Show Section Si
Title URL part use global configuration
Category URL part use global configuration
Section URL part use global configuration
Add layout to URL never
Default layout blog
Google News Settings
Google News numbering dont'use
Article ID digits 3
Custom date format ddmm
ID and date separator
ID and date ordering
Number position
Thanks a lot for the attention