On your way to where you downloaded the file(s),
you probably flew past the instructions page:
http://www.sun.com/software/solaris/download_instruction.xml
On that page it says...
" NOTE: Once you have downloaded a file, you should check that it has not been corrupted during the download before burning it to a DVD. For that, you need to do a "md5 checksum", which compares your downloaded file against the file you would find on the server. There are various free, available utilities for all popular operating systems (i.e. Windows, Solaris, Linux) that enable this. Several md5sum lists are provided on the download page ?be sure to pick the one corresponding to the files you downloaded. "
(italic and underline emphasis added)
Go back online and return to the download page.
Get the checksum that corresponds to whatever you downloaded.
Sorry, but I can't help you further.
I've never bothered with the checksums.
I download the file-du-jour, burn it to media and if it works it just works.
If it doesn't work, I expect I'd have to download it all over again.
In the last 9 years, I've never had to download a second copy of anything from Sun.