I like to manage my servers in English but my client is Polish. Is there a way to keep the main language of the server in English but get "Company Web"/OWA/Remote Access website and other publically accessible parts in Polish?
P.S. I've already installed WSS language pack - this is not the issue, the issue is to have "Company Web" and other portal contents in Polish.
WSS does not support multi-language sites out of the box, you would need MOSS for that (the feature is called 'variations'). You could create a site for each language you want to support and then use redirects to send users to the correct site. There is probably a way to "activate" the multi-language features thru custom code (like the auditing behavior), but I am not aware of anything off hand for that.
You cant change a sites language settings after it is deployed as it is part of the site template. There are tricks like backing up the site and editing the template files and redeploying the site, but this will only net you the single language change, not multiple languages for the same content.
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Try setting the default language of the server to polish and the language of your admin user to english.