SSA 2013 seems to be locking dwg files used as a background. This seems to be true if we launch SSA with the "Edit in Storm and Sanitary Analysis" command from Civil 3D or if we start SSA from scratch and add a background dwg file through the Layer Manager. To make it worse, if another user was already working in the Background drawing before SSA set it as a background, the first user will no longer be able to save in C3D.
Can someone please verify this behavior?
Any settings in SSA to prevent the file locking?
Thanks
Robert
Civil 3D 2013 SP2