Exchange 2010 on SBS server outlook clients cannot send email

one more detail. this is when they are trying to send using imap or pop3 .  They can receive but they cannot send.

Why are you using IMAP and POP3 in an Exchange/Outlook environment?!

the users are outside , they are working from a home office. How else can they work ?

By using RPC-HTTPS/Outlook Anywhere.

One of the built in features of Exchange/SBS.

See my guide here on how: https://www.experts-exchange.com/Software/Office_Productivity/Groupware/Outlook/A_3963-Open-multiple-mailboxes-on-different-Exchange-Servers-with-Outlook-2010.html see step 3

I agree with demazter, sending and receiving via outlook anywhere would be a far better solution then using pop or imap.

Or another solution would be to let the users work via OWA. The Owa included with exchange 2010 is a realy good email client.

is this going to work with IPAD's ? they are getting the error that the server cannot relay ...

For IPad's, IPhones or other mobile devices you could use ActiveSync which is designed for mobile connections.

For both Outlook Anywhere and ActiveSync it is best practice to use a trusted third party certificate.

wcreserver.wcre.net
How do i set up the active Sync ? Any ideas ?

If you have SBS and configured the server using the wizards, activesync and outlook anywhere are setup by default.

You can use https://www.testexchangeconnectivity.com/ to test if it works.

See my guide here on setting up iPhones/iPads: https://www.experts-exchange.com/Software/Server_Software/Email_Servers/Exchange/A_3211-Configure-iPhone-for-use-with-Exchange-Server.html

ok when i try to set up outlook anywhere ( when i am trying to add the user name and the exchange name and i click on check names )  it tells me that outlook has to be online or connected to complete this action.
Do i need to set it up when i am INSIDE the domain ?

Have you setup the Exchange proxy as per my guide?

What authentication method did you use? Try basic.