Hi,
The socket error points to the issue with certificates generally. My suggestion would be to take the Export of certificate from IIS server and import it to the trusted store using ThirdPartyCertificateTool.bat tool.
Try to access the image from the CM server/Dispatcher server using the URL ..../bi/sample/images (the location of images which is set for you). If the image is visible, it means that the trust is established.
If it still does not work, take an export of CA certificate in each of the Cognos CM and Dispatcher server and then import it in the IIS server. It is a 2-way approach.
Let me know if it works.
Regards
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Dinesh Agarwal
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