Hotfix Rollup 2 for Microsoft Forefront UAG 2010 Service Pack 4 is now available for download. This hotfix rollup includes fixes for the following issues:
KB3066351 – Client HTTP connections to a UAG redirect trunk receives errors after you install hotfix rollup 1 for Forefront UAG 2010 SP4
KB3070067 – You may receive an HTTP 503 “Service is Unavailable” error when a connection to a UAG trunk fails in Forefront UAG 2010 SP4
KB3068283 – You may receive HTTP 503 errors on a server that is running Forefront UAG 2010 SP4
KB3068289 – Moving mailboxes as part of a hybrid Office 365 migration fails in Forefront UAG 2010 SP4
You can download Hotfix Rollup 2 for Forefront UAG 2010 SP4 here.