KB931125 broke Lync CMS replication and conferencing

After applying KB931125 CMS replication and conferencing broke. Apparently that pushed us over the maximum size of the trusted certifcate authorities list that the Schannel security package supports (12,228 bytes). It was resolved by creating a registry key on all of the Lync servers and restarting IIS (iisreset /restart): [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL] “SendTrustedIssuerList”=dword:00000000   Thanks to Tom […]