If you use VBA inside of 32bit AutoCAD you will have noticed that it is around 1000x times slower when running the same VBA code inside of 64bit AutoCAD.
This is because AutoCAD 64bit ships with the 32bit VBA DLL in a separate out-of-process executable rather than loading the VBA DLL inside of AutoCAD itself. Therefore, a lot of marshaling is incurred communicating between the out-of-process VBA executable and 64bit AutoCAD.
Other issues you may be seeing: Run-time error ‘429’: ActiveX component can’t create object
The best solution is to install 32bit AutoCAD on 64bit Windows, here are the affected versions along with their solution text…
If you are trying to open a DWG file with AutoCAD and you get the message “Drawing File was created by an incompatible version” it’s because somewhere along the line your AutoCAD DWG files were saved with a newer version of AutoCAD.
Using Windows Explorer, copy Disk 1 of your AutoCAD 2017 install media to your hard drive, to a folder path c:\Autodesk\AutoCAD2017
If you have more CD’s, copy them all directly over the top of Disk 1, overwrite all files in your previously copied c:\Autodesk\AutoCAD2017 folder
If you have a single self extracting exe downloaded from Autodesk called something like AutoCAD_2017_English_Win_32_64bit_en-us_Setup.exe
Simply run the exe, it will ask to unzip to a folder inside of c:\Autodesk, make a note of the folder for later use (we’ll refer to it from here as c:\Autodesk\AutoCAD2017), now click OK. Wait until all of the files have extracted, when they do, the AutoCAD 2017 setup will automatically launch – simply close it and move to the next step.
Now, start the Longbow Converter tool, select the 1st tab, pick the c:\Autodesk\AutoCAD2017 folder, and click the Convert button.
Once the conversion process is complete, click Install/Run Setup to start setup. Simply install as normal.