Using anyconnect with Fortigate for client access using SSLVPN

[acrylicus]

We are having some trouble getting anyconnect to work with our new Fortigates, unfortunately due to the scale of the business we are unable to deploy new clients, and we are unable to use IPSEC VPNs. 

The Forticlient SSL VPN works just fine, but anyconnect shows "Connection failed". We have captured the following logs:

[16859:root:5a]SSL state:SSLv3/TLS write finished (x.x.x.x) [16859:root:5a]SSL state:SSL negotiation finished successfully (x.x.x.x) [16859:root:5a]SSL established: TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 [16859:root:5a]req: / [16859:root:5a]def: 0x255f690 /rmt_index.html [16859:root:5a]sslConnGotoNextState:300 error (last state: 1, closeOp: 0) [16859:root:5a]Destroy sconn 0x7f18c1e19800, connSize=0. (root)

Any help with this would be greatly appreciated.