I know that Myst IV is old, but I am planning a long trip, so I decided to install it on my netbook. The game works fine, but when I try to install the patches I always get the error message "Could not retrieve installation folder! Installation will be aborted."
This happens for both the 1.02 and 1.03 patches. I run XP home edition SP 3, Myst IV is installed in the default directory c:\program files\ubisoft\Myst IV - Revelation.
I really would like to install the patches because of the subtitles and since it seems that some puzzles cannot be solved without.
Any suggestions? Thanks in advance.

Did you try reinstalling the game ?

No,since the game is working fine, I did not think of that. I did a "minimum" instllation: could that be the cause of the problem? Should I do the "normal" one (the one that uses more disk space)?

Revelation will play more smoothly if you do a normal/full install.

When you apply the patches:
-- a. Copy the downloaded patch files to your C:\program files\ubisoft\Myst IV - Revelation folder.
-- b. Apply *both* of the patches from that folder using Start > Run.
----- 1. Log into Windows with full Administrator privileges, and close all open applications.
----- 2. Run myst4_v1.00_to_v1.02_pc.exe first, then run myst4_v1.0_to_v1.03_pc.exe.
----- 3. Follow the install Wizard's instructions, and accept the install defaults.

I followed the instructions, the installation wizard asks me which language I want, I accept English, it starts "preparing the InstallShield Wizard", and then it always gives me the message "Could not retrieve installation folder! Installation will be aborted".
Yes, I have administrator privileges.
Do you know how it looks for the installation folder? Does it use the registry?
Thanks!

To save time, you can skip the patch to 1.02 unless you absolutely want a new registration app.

Well realXCV was correct, reinstalling the game did the trick. After that I could install the patches with no problem.
Thank you all for your help.