Error running all business processes

Hi all, 

Does anyone have a clue why the following error would appear when trying to run any business process? All our business processes suddenly stopped at 01.00 on Sunday night.

I have asked support, but received an estimate resolution of 2 days, so asking here in the hope someone has seen this before as currently the system is unusable. 

And on that note. Does anyone have any suggestions on what they do in these situations? 2 days seems a bit ridiculous when 40+ users are unable to do their jobs!

Thanks!