In the below documentation of "CA Single Sign On Agent for SharePoint 12.52SP1", a registry key EnablePagingADNameSpace is explained for Policy Server.
Enable Paging for Searches of Active Directory User Stores (64-bit systems)
However, the documentation of SiteMinder 12.8 does not have it. Is the registry key applicable to 12.8 or earlier release?
Release : 12.8
Component : SITEMINDER - POLICY SERVER
Yes. The registry key EnablePagingADNameSpace is applicable in Policy Server 12.8 as well as earlier releases.
Here's an excerpt from the document for 64-bit systems:
The Active Directory namespace does not support paging, causing searches of more than 1000 users to fail. To support searches of large numbers of users in the Active Directory namespace, enable the following registry key by setting it to one:
To enable paging for searches on your Windows Policy Server:
1. Open the Windows registry editor.
2. Locate the following registry key:
3. Set the value of the key to 1.
Restart your Policy Server.