We are a consulting engineering firm using AutoCAD 2008, we have
recently noticed that on a number of .pdf files that some of our
information is missing. Could this be because the .dwg doesn't fully
regenerate before plotting? If this is the case, how do we stop it
happening? If not, are there any other ideas on how to rectify this
problem?

[QUOTE=BarbaraKathari]We are a consulting engineering firm using AutoCAD 2008, we have recently noticed that on a number of .pdf files that some of our information is missing. Could this be because the .dwg doesn't fully regenerate before plotting? If this is the case, how do we stop it happening? If not, are there any other ideas on how to rectify this problem? [/QUOTE]
 
 
Maybe you should check some  features of them ex. layers , xref-s,size ect.

What information is missing? (!)  Is this on a layer that is set not to plot?If you attempt to plot the drawing and check a Preview, is the information there, or is it also missing?  If it's missing on the Preview, then it's more than likely that it's on a layer that isn't set to be plotted.  Check what layer the offending item or items are on and then check using the Layer Manager.HTH

we had similar issue in our office. But the problem was with version of acrobat reader used. We are using for pdf creation acrobat 7. When we opened some drawings in reader 6 or 7, some objects were missing or we had some straight lines thro the drawing. When we used reader 8 or 9, the drawing was as expected.
So my advise is to try to open it in reader 9 if it is not just reader failure.

I am using DWG to PDF Converter by Autodwg.com, it converts my dwg files to pdf files easily and quickly, free trail of DWG to PDF converter software is available for download form here: http://www.autodwg.com/PDF/I did download and run this application for almost one year, nothing lost.

Please avoid using any external DWG-to-something convertes. Only AutoCAD can understand all types of entities and information inside DWG files.
 

When you use the native AutoCAD export to PDF or a virtual PDF printer to print your drawings from AutoCAD, no information will be lost (you can also use it to batch convert DWGs to PDF). Any external tool will loose some information as it cannot fully understand the DWG file format.

[QUOTE=GaryMichael]I am using DWG to PDF Converter by Autodwg.com, it converts my dwg files to pdf files easily and quickly, free trail of DWG to PDF converter software is available for download form here: http://www.autodwg.com/PDF/I did download and run this application for almost one year, nothing lost.[/QUOTE]Why?  Use cutePDF instead, it works (as a printer driver) and doesn't cover the output in watermarks or identify it as having been printed with cutePDF..