Well hell:
Has a clever ring to it, doesn't it.
The
First thing you should do when you have a reversing problem is GO TO THE SEARCH BUTTON and/or YOUR FAVORITE SEARCH ENGINE and actually seek out answers to your OWN problems. Have you searched here for "shrinker" (without the quotes) or on the net using "shrinker 3.4 unpacking" (again without the quotes). You might then discover that there are a couple of flavors of shrinker unpackers already on the net. (Doh!)
It is also a GOOD IDEA to go to the website of the product maker and read what they have to say about their product. It often gives you GOOD CLUES about problems you might experience. Such as:
"As an added bonus, Shrinker's compression even encrypts computer software to act as an effective protection against decompilers."
Now here's another "mystical statement" you can write on your wall.
Encrypted code won't run, the program has to decrypt itself at some point, and at least to some extent, to work at all. Parts might be encrypted and only decrypted if "registered" or a "password" is entered, but, the general program has to decrypt (and unpack) itself to run. Where the code does that can often be discovered and used to decrypt the program for you.
Or if you are too lazy to do your own learning
you could find one of the tools for unpacking/decrypting shrinker 3.4 and let it do the work for you. One such, which I found with only a few minutes searching, has an option: "unpack Shrinker 3.4, decrypt", but if you want to "learn," you might want to read some of the may tuts on the net and examine the Tools to see how they did it for you. That's what "learning" is all about.
Regards,