Thank you for your fast answer, Sakin.
The English strings in the screenshots are enough, because the only clear messages returned are “Forbidden”, “Forbidden Access” and “Error 403” when saving a post, and “Error 404” when uploading an image. The Italian parts of the screenshots are not relevant.
Two sys admins my friends suggested me few hacks with mod_security in the .htaccess file, but the only results were “500 Internal Server Error”:
SecFilterEngine Off
SecFilterScanPOST Off
------------------------------
<Files xmlrpc.php>
SecFilterInheritance Off
</Files>
------------------------------
<IfModule mod_security.c>
SecFilterRemove 114
</IfModule>
Here some old talks on a similar problem:
http://ios.forums.wordpress.org/topic/cant-access-blog-via-app?replies=16
The blog I’m talking about is http://www.placidasignora.com/, self hosted in a normal shared hosting.
I must add that both my two friends have many blogs and they usually post through iPad and iPhone without any problem. Some of their blogs are http://www.spinoza.it/ http://eiochemipensavo.diludovico.it/ http://www.andreabeggi.net/blog/ (this latter is on my very same hosting!)
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