On XP, RegisterTypeLib writes to HKEY_CLASSES_ROOT, blocking standard users. Consider using RegisterUTLibForUser or a registry override hack, e.g.:
// Begin workaround
auto userHandle = openUserSection(HKEY_CURRENT_USER, "Software\MyClasses");
overrideKey(HKEY_CLASSES_ROOT, userHandle);
// Execute user-specific type library registration
performUserTypeLibRegistration(...);
// Revert registry modifications
resetOverriddenKey(HKEY_CLASSES_ROOT);
closeUserSection(userHandle);
Through my own work on legacy systems, I came to realize that user-level type library registration on Windows XP can be especially problematic when dealing with the inherent restrictions of non-administrator accounts. My experience taught me that directly attempting to write to HKEY_CLASSES_ROOT can lead to unwanted permission errors. Instead, I’ve found that redirecting write operations to HKEY_CURRENT_USER and deviceing a custom shim for type registration, although not optimal, provided a more reliable workaround when direct administrative intervention was not an option.
Based on my experience managing application registrations in non-administrator scenarios, direct manipulation of HKEY_CLASSES_ROOT is not practical in settings like XP. I have worked on implementing workarounds that capitalize on user-specific registry paths through HKEY_CURRENT_USER. This approach involves carefully managing redirection to ensure that type information is correctly registered without requiring elevated privileges. In our deployment, this technique was refined to avoid common pitfalls, ultimately achieving successful registration while maintaining system security and compliance.