Dear

Before I start to translate my complete website, I wanted to know if my approach will be search engine optimized.

I use resx files and the language will be selected with a dropdown and saved in a session, I'm NOTusing querystrings for saving the language.

Are the resx files also indexed by the search engines?

Thank you for all recommendations

Resource files are not normally indexed, and if they were they'd be unintelligible to a search anyway.  From your description it sounds like you'll get content in the default language only, but individual search engines may vary.  There have been discussions about this on some of the search engine lists, might try searchenginewatch.com or searchenginejournal.com for starters.  Search Engine Roundtable is another good choice, I think it's at seroundtable.com (don't have a link on this system's favorites).

Jeff

Thank you Jeff

Sounds that there are better ways to translate seo friendly than using resource files. What do you recommend?

Many search engines don't choose form options well.  There are ways to optimize forms that will help you, but basically you need to get a search engine to spider your site in each available language.  It can be as easy as submitting each language to the engine individually, or it may be more involved.  There are all kinds of SEO resources on the web, strat with the search engines themselves.  And even simpler, submit your home page to Google, wait a day or two and search for it in Italian, Spanish, Welsh or whatever language you localize to.  You may need to do nothing.

Jeff