In my current game i got a error at one point. As far as i know nothing out of the ordanry was going on.
However after this non of my workers want to build. They harvest, craft and gather. They mine, but they refuse to build. Even a simple new building they refuse.
THe error pops up when i load the game, initially the workers get a “building” word but right after the error all of the them turn to idle and they walk back from the building job 
release-779 (x64)
@stonehearth/components/ai/ai_component.lua:560: (6476222 stonehearth:racoon) has not yielded after 10 ai spins. Are they in a bad state? Last abort reasons: <follow_path mover aborted reason: could not compute full path in start. (x10)>
stack traceback:
radiant/modules/commons.lua:46: in function 'report_traceback’
radiant/modules/commons.lua:230: in function 'verify’
stonehearth/components/ai/ai_component.lua:560: in function <stonehearth/components/ai/ai_component.lua:499>
[C]: in function 'xpcall’
radiant/modules/commons.lua:66: in function 'xpcall’
stonehearth/components/ai/ai_component.lua:499: in function '_thread_main’
stonehearth/services/server/threads/thread.lua:273: in function <stonehearth/services/server/threads/thread.lua:270>
[C]: in function 'xpcall’
radiant/modules/commons.lua:66: in function 'xpcall’
stonehearth/services/server/threads/thread.lua:270: in function 'f’
radiant/lib/env.lua:15: in function <radiant/lib/env.lua:14>