I have intalled new version - 2.0. And all of my DKP values are empty now. How can i restore DKP? Can my officer send me his old dkp table? And how to evade this problem in future

If you're not an officer, it's supposed to delete everything. Your officers will send you the migrated tables.

Im Guild Master

Nothing should have been deleted for you then, unless someone else did the migration and you selected to wipe tables. Best option would be to restore a backed up saved variables file and use 1.6.2 until the kinks in 2.0 are worked out. Or another officer that still has 1.6 can broadcast those to you