1. Navigate to Program Files (x86)\Common Files\Micro Focus\NMShared\5.5 (or highest number present) and right clicking on wcore.dll and select Properties
2. When the properties window opens please select the 'Digital Signatures' tab.
3. Select the signature listed in the signature list and click the 'details' button
4. Near the top of the tab look for 'Digital Signature Information', underneath is the status of the certificate
5. If your certificate is valid, it should read, “This digital signature is OK”
6. If your certificate doe not state the digital signature is OK it will require updating.
Please see this link for more information: http://technet.microsoft.com/en-us/library/cc734054(WS.10).aspx
However, your network admin may have a group policy that is preventing the download of updated root certificates.