What are the Softwares whose links are not found.
Please update the Question.
I will try & get them for you.
Now the reasons:
1. Either the software is not freeware, or if it is then it might be linked to a site which is paid, or which is no longer available.
2. If the softwares are uploaded to pirate sites, then the links will not work or may have been deleted by the site, or by the owner.
3. If the software is shareware, then there would be a link somehwre or other.
4. Apart from this, you need to check, if the software is still there or in run, if not, then the software might have become obsolete.
Please do list which are the ones, you are unable to locate, & I will try & locate for you.