In edit/preferences/privacy I have lost details in "Identify Browser as" box and there are no items in drop down menu. Subsequently certain sites I cannot access any ideas as how to get them back?
Baz

well, if these lines are missing from your prefs.js file, you should add them:

user_pref("kmeleon.privacy.useragent0.name", "Default");
user_pref("kmeleon.privacy.useragent0.string", "");
user_pref("kmeleon.privacy.useragent1.name", "Netscape 6.1");
user_pref("kmeleon.privacy.useragent1.string", "Mozilla/5.0 (Windows; U; WinNT4.0; en-US) Netscape6/6.1");
user_pref("kmeleon.privacy.useragent2.name", "Netscape 4.76");
user_pref("kmeleon.privacy.useragent2.string", "Mozilla/4.76 [en] (WinNT; U)");
user_pref("kmeleon.privacy.useragent3.name", "MSIE 6.0");
user_pref("kmeleon.privacy.useragent3.string", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)");
user_pref("kmeleon.privacy.useragent4.name", "MSIE 5.5");
user_pref("kmeleon.privacy.useragent4.string", "Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)");
user_pref("kmeleon.privacy.useragent5.name", "MSIE 4.0");
user_pref("kmeleon.privacy.useragent5.string", "Mozilla/4.0 (compatible; MSIE 4.0; Windows NT)");
if they aren't missing, then i don't know what's wrong.

wow - that formatted incredibly badly.

those should all be single lines (beginning with 'user_pref') in reality.