I installed solaris virtually and tried to format the partitions .. I dont know what went wrong, It got rebooted and hangs in the screen "No partitions" and after pressing Enter button it goes to "INT18 boot failure" and hangs there once again . Could any one of you suggest why this has happened and how to come over this? If I didnt get any solution I can delete it and install a new one 
Thanks
Priky
I didnt get any reply for this. SO I booted it from the CD and entered in single usermode.
single-user? meaning your system is not fully up with its services... better re-install. It should come up in multi-user. Try doing some filesystem checks in single-user, if its still the same with no better outcome, re-install
I would run a diagnostics on the Hard drive to definitely determine if it has gone bad.
Hard Drive, External Drive and Portable Drive | Maxtor.com
IBM - United States
Hitachi Global
FUJITSU
Seagate Technology
Ireland - SAMSUNG
try some of those sites there for some Hard drive diagnostics programs.