I had my wallet (qt) working normally. However, since a few weeks I receive no blocks anymore (282322 from 286293 are generated, last block was 3 weeks ago).

I’ve updated the last version. I have 8 working connections to the Bitcoinnetwork.

On top off my wallet I get the message: “Warning: Shown transactions are possibly incorrect! Perhaps you should upgrade, or other nodes should upgrade.”
How can I resolve this?