I have been using jetpack for all the scienceblogs.de-subsites, and it has been working well for a few weeks. But suddenly (could there have been a system upgrade?) it stopped. WP dashboard shows that Jetpack is installed and activated for all the blogs; but none of the functions - we use Jetpack for comment subscriptions and LaTeX integration into blogposts - are available on the site. Uninstalling is also not an option - the network environment plugin page prompts for either deactivation or editing; the former does not help, since reactivation does not show any effects, and to mess with the code is beyond my software savvy. So how can I start over? Is there another version that I can upload and which overrides the current installation? Or can I make adjustments to the code - and when: what do I change where?
We are using WP 3.4.2 and Jetpack 1.8.2, which seems not a very reliable combination. Any other tips for frustrated (and desperate) users like me?