View Full Version : Reverse compression results using InstallShield Pro 7 and vBuild 2

11-11-2003, 02:50 PM
So I was asked to add some files to my existing installation created using InstallShield Pro 7 (latest updates and hotfixes) and vBuild 2 (latest updates and hotfixes). To my surprise, the vBuild version grew larger than expected.

I am using vBuild to create a full version of the original installation (no updates or online package). I am adding 75 .NET interop files, with a raw file size of 3,346,432 bytes. Here are my results.

Install (no vBuild compression)
Before addition of new files = 31,054,619
After addition of new files = 31,942,191
Difference = +887572

Install (with vBuild compression)
Before addition of new files = 20,238,854
After addition of new files = 21,189,723
Difference = +950869

What's going on here? Why exactly is the addition of these files causing a 950K increase when using vBuild, but only an 888K increase without? Is there some sort of reverse compression going on?

11-12-2003, 01:56 AM

Can you send me the added 75 .Net interop files for inspection? (I do not need the entire media for now, just the files in a zip). If this is ok, please e-mail it to alon@redbend.com


11-12-2003, 02:00 PM

I just sent you the ZIP file containing the files in question. Thanks for following up on this matter.

- Mark

11-13-2003, 09:09 AM
We have found the reason for the "reverse compression" - these are .net dll's that we do not handle correctly in vBuild 2.1. This will be corrected in the next version/service pack and the result for these files will be about 600K.