How to detect if a Win7 install DVD contains 32bit or 64bit version?

We have bought some month ago 32bit and 64bit versions of Win7.
From one of them we burned a backup DVD.

Now we need to re-install Win7 on a computer but we did not found the original DVDs. Fortunately we have the backup DVD available.

Is there a way to find out if it contains the 32 bit or 64bit version?
Of cause without trial and error by installing it. Just from inspecting the files.

We found no info/readme file on it which shows the version.

Peter

pstein said:

We have bought some month ago 32bit and 64bit versions of Win7.
From one of them we burned a backup DVD.

Now we need to re-install Win7 on a computer but we did not found the original DVDs. Fortunately we have the backup DVD available.

Is there a way to find out if it contains the 32 bit or 64bit version?
Of cause without trial and error by installing it. Just from inspecting the files.

We found no info/readme file on it which shows the version.

Peter

If it is the same as the original 32bit is about 2.5 gigs (the ISO) and 64 is a bit over 3 gigs.

Quick. The one with the largest contents is the 64 bit.
If you have lost the very expensive originals, I hope you have not lost the keys which came with them.

davehc said:

Quick. The one with the largest contents is the 64 bit.
If you have lost the very expensive originals, I hope you have not lost the keys which came with them.

Hmm, we have only ONE DVD and we cannot compare them with another or the originals.

Instead of calculating the DVD content size I would prefer to

- inspect the size of a certain core file or
- read an entry in an info text file content or
- view the 23th byte of file xxxxx.dll or
- call a certain setup.exe file with parameter -version
- or something similar.

Is there really no such inherent, fool proof solution?

Examine the root and open the autorun.inf file with notepad.
The 64 bit version shows:[AutoRun.Amd64]
open=setup.exe
icon=setup.exe,0

[AutoRun]
open=sources\sperr32.exe x64
icon=sources\sperr32.exe,0

The 32 bit version shows:[Autorun]
open=setup.exe
icon=setup.exe,0

Seems he does not have both on the one dvd, so nothing to compare.

I believe Zigzag has already suggested that.