Client Access is a nontrivial, PC-based, client server suite of applications. It makes extensive use of the registry. The installation program creates many registry keys. The application must not be restricted from its own keys. It is not expected that any application works successfully in such an environment. Following is a list of registry keys that Client Access requires access to:

 

HKLM\Software\IBM\Client Access\
HKCU\Software\IBM\Client Access Express\
HKLM\SOFTWARE\Microsoft\Cryptography\RNG\
HKCR\
HKLM\Software\Microsoft\
HKLM\System\CurrentControlSet\

IBM suggests that these keys retain default settings. While most of these keys are accessed for READ, the first three are also updated. If the user signed on Windows cannot write to the first three keys listed, Client Access will not work.