Pipe Elevations keep resetting

[pst1]

I have a drawing with number of pipes, networks & profiles and the pipe elevations keep resetting.  The reset elevations are often much lower than they're supposed to be.  Sometimes the elevations are completely off the profile grid.  See attached.

The red lines represent the correct pipe location.   It happens often enough that I've put in the red polyline where the pipes are supposed to be so I can just drag the pipe back to their proposed location.  Not all the pipe reset either.  Sometimes 50% of the pipes reset and other times its about 80% but never all of the pipes. 

I actually caught it once and I was drawing a polyline in the job and noticed the drawing paused like it was autosaving but when I didn't see anything in the text window that referenced an autosave, I checked the profiles and sure enough, the pipe had reset again.  So it wasn't like I was modifying a pipe or structure in another part of the drawing,  In this instance, I was able to simply type undo and it put the pipes back  to their original location but most of the time, you don't catch it.

The drawing started out in version 2016 and now we're using 2021.  I've tried bringing everything into a new drawing to see if that fixed the problem. I've erased the pipes and re-defined them  but it persists.  I haven't had this problem with any other drawing.

Anyone have any idea how to fix the problem?

Thanks

[lim.wendy]

Hi @pst1 ,

Thank you for reaching out in the Autodesk Forums. This is a great platform where you and the rest of the community can benefit. 

This could happen if you are using an older version and then move to a newer version, please check out the article below:

Error: Unable to run macro for "C3DPipeNetworkRules.dll"

See similar posts below:

C3D 2018 Pipe network change elevation automatically.....

Pipe Inverts Changing, Shifting

If you're using reference template, see this post: AutoCAD 3D 2019 pipe network issues

Hope that helps! Let us know how it goes!

[Anonymous]

I have this same exact problem.  I have 4 roadway drainage pipes that drop ~50 ft. in the profile.  It's hard to catch at times, as it occurs after random edits to my drawing.  Like you, I had to draw a centerline to draw the correct placement of where the pipes should be.