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Thanks for replies, at least I know what's going one.

This is really frustrating and hard to explain to users. I can understand that nothing can be perfect and every system has it pros and cons. But I can't understand the fact that functionality that we use is suddenly corrupted and useless anymore. Does anyone know how Microsoft explains these changes? How can you use this system for business critical solutions when this is happening all the time? This is at least 4th case in our organization for last year.