Whether it's coincidence or not but since upgrading to Lion OS I find several of my third party apps do not update any more. I find Picasa, Google Chrome, Mozilla Thunderbird and my TomTom satnav won't update via my Mac. I have checked all my prefs but cannot figure out why. Is there something I should check to see if there is a block. Everything else works fine, Safari, Macmail all connect ok. Would appreciate it if anyone can help.