I scanned with Trend Micro PC-cillin v 15.30.1151, and McAfee's very own Viruscan Enterprise 8.0, Other people have reported they scanned with Norton Antivirus, ClamAV 0.94.1/8645, avast! v4.8 Home Edition and found mailsend is clean.
The site: http://www.siteadvisor.com/sites/muquit.com/downloads/6455549/ claims that mailsend modifies registry:
CHANGE [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Prefetcher]
This is just insane!mailsend does not have any code to mess with registry.
Here is my opinion on this:
Whoever reported that mailsend is a virus, was infected with Gaobot and mailsend was corrupted. I know the program is not corrupted and it has no code to mess with registry, so I think this explanation makes sense. It is also quite possible McAfee's software is just outright buggy.
If you have a better explanation, please post your comment.
If you are interested to verify, I am leaving the original file: mailsend1.15b5.exe.zip (available at the mailsend page).
MD5 sum: deb005aee615bbcae84fd9d87b8d6e8d
Check the bottom of the SiteAdvisor page and check the size nd MD5 sum to make sure you are dealing with the same file.
Please verify with your Virus scanner and post your comment, I would appreciate it!.