An error has been detected in Sitecore 8.1 (update 2), and this hotfix in the support team:
- "/sitecore/client/Applications/Launchpad/PageSettings/Buttons/ContentEditing/ExperienceEditor"
- "" :
? /Sc _mode = & sc_resolvelanguage = 0
:
. https://kb.sitecore.net/, dropbox: