Problem -- downloaded pets won't come out, even though they're not corrupt.  

Q: I adopted a mixed breed who needs the Irish Setter.dog and the Beach Dog.dog 
breedfiles.  I have these breedz. Both breedz work perfectly out of the adoption center, 
yet an error message saying that I do not have the right breedfiles always comes up when 
I try to bring this downloaded pet out.  I made absolutely certain they worked and the 
names were spelled the same. I attach the pet.

A: Okay, your problem does lie in the breedfiles.  The pet expects the two 
 breedz not only to have the correct name, but also to have the correct 
 ID numbers.  The Beach Dog's ID number should be 8740, and the Irish 
 Setter's ID number must be B705.  Make sure that those two are correct, 
 and your pet will come out amd play :-) 
  
 If your breedfiles don't have those numbers, and you have gone and 
 adopted other petfiles from them, you will be able to bring out both those 
 pets and this one if you rename one of the Beach Dog.dog breedfiles to 
 Beach Dog.dog2 and one of the Irish Setter.dog breedfiles to Irish 
 Setter.dog2 

Q: how do you tell what offset bytes the pet is looking for?

A: You find the ID 
number fairly easily if the pet has more than one breed; search for YALP 
and in Archey it was like this: 

00033872 0000 0000 0200 0000 8740 1C00 0000 5C52 .........@....\R 
00033888 6573 6F75 7263 655C 446F 677A 5C42 6561 esource\Dogz\Bea 
00033904 6368 2044 6F67 2E64 6F67 B705 1F00 0000 ch Dog.dog...... 
00033920 5C52 6573 6F75 7263 655C 446F 677A 5C49 \Resource\Dogz\I 
00033936 7269 7368 2053 6574 7465 722E 646F 6770 rish Setter.dogp 
00033952 2E66 2E6D 6167 6963 7065 747A 4949 4900 .f.magicpetzIII. 
00033968 0000 0000 0100 0000 5941 4C50 1E00 0000 ........YALP.... 

Now, see this, before the first breedfile pointer: 8740 1C00 0000?  
Well, the first two numbers there are the ID number.  Then with the 
Irish Setter  there's this: B705 1F00 0000 and the first two numbers are 
again the ID number. 

If your pet only has one breedfile, sometimes the number is not placed 
there, you then have to search in a more obscure place for the number. See
my Changing the breed in a petfile "howto" for more details.