Error accessing the registy when importing registry key

I am in the process of replacing a machine with a new one. Both are XP Pro desktops. The old machine has some software on it that was purchased but the install CD is no longer available and the vendor will not replace it. This machine is being used by a friend in a small business and I am trying to help him out. This is an area I have no expertise in so please forgive my incorrect use of terminology.

From looking at the old machine I found a number of registry entries relating to this software. So, what I theorized is that if I can export the associated registry keys from the old machine and import them into the new machine, the application should function. Sounds like a serviceable theory at any rate. I found 16 registry entries. The bulk of them import just fine.

There are several that I am having problems with. When importing these to the new machine, I get an error message "Error accessing registry ".


I notice several things: In all cases of entries that will not import, they are in HKEY_CURRENT_USER. The top level folder structure that is being imported is not present in HKEY_CURRENT_USER. When I tried exporting/importing at the lower level key I got the same message so I tried exporting/importing at the higher level and it yielded the same message

The old machine has a folder structure of
HKEY_CURRENT_USER
S-1-5-21 ... -1005
- and -
S-1-5-21 ... -1005_Classes

The new machine has a folder structure of
HKEY_CURRENT_USER
S-1-5-21 ... -1004
- and -
S-1-5-21 ... -1004_Classes

The essential difference being the two folders that end in _1004 and _1005
Have any of you run into this before or have any ideas for me? Is this somehow related to different user id's? I am in a bit over my head here and need some help.