I think that some lines may have come from an AutoCAD file that was saved in dfx format. however, version 2.2.2 can open and save the file with no issues, 95% of the work was done in QC 2.2.2. I just opened the file in QC 3 and tried to do a save as, because I have been using QC 2.2.2 on this file for some time, I don't think I have the imported file.
I have had exactly the save problem with files created under Qcad 188.8.131.52.
(win7, 64bit). The problem seems to develop when you start manipulating/ deleting layer or blocks...the end result is usually a zero bit file.
when i try to any of my current QC 2.2.2 files, I get the same dialog box. I even trid a file that has no entities just layes and it does not allow me to save the file. I will send you a few files. what addess would you like me to send then to?
I found a solution, I right clicked on the QCAD icon from my desktop in windows 7, chose properties, selected the compatibility tab, then checked the run program compatible mode box, and then chose windows xp service pack 3. It will now allow me to save the files.!!!
I struggled with the same problem but under XP 32bit
Andrew figured out it was a wrong named Layer and the same in Blocks.
In my case I used quotation marks in the names like Frame 1"=16".
After I renamed the Layers and Blocks in something without quotation marks it was easy to save the files ...