How to protect autocad file

I need to protect autocad files for modifying (but drawing must be
plotable!).
What are the possibilities? Is there any option in autocad (like password
protection) or conversion in other formats?
I tried with conversion into PDF, but then the problem is plotting that
file. I don't want to plot in file because it should be plottable on all
plotters.

tnx

 

PDF files are easily plotted. Why would you think otherwise?
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I made pdf with Adobe Acrobat 5.0. Plotting a small drawing (A4,A3 format)
on my laser printer is ok. But when I tried to plot big drawings (A1,A0
format) on plotter (I don't have my own plotter, but I sended to a several
specific shops who does plotting drawing from autocad format, and they
couldn't get big format on their plotters (biggest was A3 format). One
plotter was HP, and the other one was Kayocera.
How did You plotted and which plotter did you use?

 

You must set up a custom sheet size in Acrobat before creating your PDF.
Then have your outside shop plot at 1:1. It doesn't make any difference what
plotter is used. We do it all the time.
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