Can't add/use lock screen widgets

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http://forums.androidcentral.com – Hi. I am unable to add or use lock screen widgets. In the lock screen settings menu I have no option to add apps/widgets (the option is missing) and lock screen widgets menu "Favourite apps or Camera" is greyed out. All these options is available (and works) after a fresh restore but it seems to disappear as soon as I use the Google Play Store... Carrier is Three (UK). Any advice? (HowTos)