The issue being discussed in this article is:
When checking for updates on an SI Client, you get the "Access is denied" error message.
The message will appear when you click Start > Help > Check for Updates.
The following is the cause:
Lack of Administrative Windows permission.
The following is the resolution:
1/ Close the SI Client, right-click the icon, and select Run as administrator.
2/ Then, run Check for Updates again.
The update screen should pop up so you can complete the update.
If you cannot resolve this issue, please open a Support Ticket.