HI Krishna,
As I have installed 10.2 M030 on 6 servers till now and every time I found this issue except one server.
As per me, this is a Bug. After cognos installation, it creates a windows service as cognos, but does not get started automatically during installation process and then installation shows as failed for both cognos and language pack.
I found a workaround for this issue.
when installation fails, start Cognos service from windows services-cognos-start. Confirm services started.
then again run the psi and this time select recover failed installation. Installation will be successful.
Regards,
Shekhr