Check the following:
When attempting to send traffic check the output of ''sh cry ips sa'' to make sure packets encrypted/decrypted increments.
Could be that NAT-T is not configured.
Check the configuration for:
crypto isakmp nat-t
sh run all sysopt--> should show sysopt connection permit-vpn
Add the command
And try to PING the inside IP of the ASA from the VPN client.
Let's take it from here...