This limit has been imposed to prevent spam attacks on servers from clients who exploit this if they get authenticated access.
The way it works is that, if a spammer gets authenticated access to a mailbox, he can send multiple spam mail in one connection (upto the limit of max recipient count) and repeat this, thus flooding the queue with junk mail. Another way this happens is that the client PCs (typically those having MS Outlook) can get infected with viruses and these viruses send mail via the server (without the user’s knowledge).
To prevent such spam attacks (which are very common), we have imposed a restriction on the maximum number of recipients in a single mail. This is a common practice and is followed worldwide by leading mailing companies e.g.
We suggest that if you want to send mail to multiple recipients
1. You may make a Group (distribution list) with your contacts and send a single mail to the DL. There is no limit on how many recipients can be added to the DL/Group
2. You could use a bulk mail software application on your desktop (there are several free ones too) to send mail to multiple recipients, one at a time. Mind you but this would be limited to the maximum number of mail allowed for a single sender.
3. You may use the services of a bulk mailing service if you have a large number of recipients for your mail.
For more information about the limits imposed by MithiSkyConnect, please visit this link