How to prevent automated workers from destroing mana nodes

[sengfossil]

as topic says:

My automated workers always try to replace the mana nodes with their buildings. Do I have to control them all manually now ?

Any hints are welcome. Tx

 

[Blankk]

there's an option in the options menu that'll say something like "workers will not build over existing improvements" or something. Check that box before playing.

 

[sengfossil]

ah , forgot about that. ty