I thought it might be useful to provide a summary list of DirectAccess related hotfixes from the past and present that may be of use to those embarking on a DirectAccess deployment for the first time, or those experiencing problems that have been solved already!
PLEASE NOTE: Microsoft have now provided an official dynamic knowledgebase article which provides a summary of Windows 7, Windows 8 and Windows Server 2012 hotfixes which can be found here: http://support.microsoft.com/kb/2883952 and consequently supersedes the below information.
Last updated 14/08/13 with KB2849568.
Hotfixes: Windows 8 and Windows Server 2012
KB2859347: IPv6 address of a DirectAccess server binds to the wrong network interface in Windows Server 2012.
KB2855269: Error message when you use an account that contains a special character in its DN to connect to a Windows Server 2012-based Direct Access server.
KB2849568: Vulnerability in the Windows NAT driver could allow denial of service: August 13, 2013.
KB2845152: DirectAccess server cannot ping a DNS server or a domain controller when a DirectAccess client is pinging the same server in Windows Server 2012.
KB2844033: DirectAccess Setup Wizard fails on a Windows Server 2012-based server in a domain that has a disjoint namespace.
KB2836232: Subnet mask changes to an incorrect value and the server goes offline in DirectAccess in Windows Server 2012.
KB2796394: Error when you run the Get-RemoteAccess cmdlet during DirectAccess setup in Windows Server 2012 Essentials.
KB2795944: Windows 8 and Windows Server 2012 cumulative update: February 2013. This update includes fixes for DA that provide stability under heavy load.
KB2788525: You cannot enable external load balancing on a Windows Server 2012-based DirectAccess server.
KB2782560: DNS64 does not resolve computer names when you use DirectAccess and external load balancing in Windows Server 2012.
KB2769240: You cannot connect a DirectAccess client to a corporate network in Windows 8 or Windows Server 2012.
KB2748603: The process may fail when you try to enable Network Load Balancing in DirectAccess in Window Server 2012.
KB2666914: DirectAccess Connectivity Assistant 2.0 is available.
Hotfixes: Windows 7, Windows Server 2008 R2 and Forefront UAG 2010
KB2797301: A Forefront Unified Access Gateway 2010 DirectAccess client experiences repeated OTP prompts.
KB2796313: Long reconnection time after a DirectAccess server disconnects a Windows 7-based DirectAccess client.
KB2758949: You cannot build an IP-HTTPS protocol-based connection on a computer that is running Windows 7 or Windows Server 2008 R2.
KB2718654: You are prompted to enter credentials when you try to access a SharePoint server on a Windows 7 SP1-based or Windows Server 2008 R2 SP1-based computer.
KB2680464: Location detection feature in DirectAccess is disabled intermittently in Windows 7 or in Windows Server 2008 R2.
KB2663354: DirectAccess Manage Out fails for any non-ICMP traffic in Forefront Unified Access Gateway 2010.
KB2633127: DA client cannot reconnect to the UAG DA server when a Windows 7-based or Windows Server 2008 R2-based client computer is connected to the Internet.
KB2615847: "ERROR_IPSEC_IKE_CERT_CHAIN_POLICY_MISMATCH" error when you try to start an IPsec connection between two computers that are running Windows 7 or Windows Server 2008 R2
KB2535133: IP-HTTPS clients may disconnect from Windows Server 2008 R2-based web servers intermittently after two minutes of idle time.
KB2444558: You cannot access a host that is hosting the IPv4 file share by using SMB v1 from a Windows 7-based or Windows Server 2008 R2-based DirectAccess client.
KB2288297: You are unexpectedly prompted to enter your credentials when you try to access a WebDAV resource in a corporate network by using a DirectAccess connection in Windows 7 or in Windows Server 2008 R2.
KB979373: The DirectAccess connection is lost on a computer that is running Windows 7 or Windows Server 2008 R2 that has an IPv6 address.
KB978738: You cannot use DirectAccess to connect to a corporate network from a computer that is running Windows 7 or Windows Server 2008 R2.
KB974080: DirectAccess Workaround for reaching IPv4 address checking sites.
KB973982: The certificate for IP-HTTPS does not rebind if the certificate is changed after the configuration is applied one time in Windows Server 2008 R2.
KB972516: A DirectAccess access failure occurs after the DNS servers that are running Windows Server 2008 return empty responses for AAAA queries in a WINS zone.
Security Updates: Windows Server 2008 R2 and Windows Server 2012
Hope the list is useful!