We have been experiencing Mapi session limit lockouts for all out VPN users. We have increaed the session limit from 32 to about 70 for some users and still having the issue. We have been rebooting the server to correct the issue. Does anyone know a root casue, could VPN 4.0 be the culpret? We have checked all users and can not find anything they have in common with other. Please help we are currently running Outlook 2003

Apply this patch: 948496 An update to turn off default SNP features is available for Windows Server 2003-based and Small Business Server 2003-based computers http://support.microsoft.com/default.aspx?scid=kb;EN-US;948496 And add this registry setting: Value name: KeepAliveTimeKey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\ParametersValue Type: REG_DWORD-Time in millisecondsValid Range: 1-0xFFFFFFFFDefault: 7,200,000 (two hours)This value controls how frequently TCP tries to verify that an idle connection is still intact by sending a keep-alive packet. If the remote computer is still reachable, it acknowledges the keep-alive packet. Keep-alive packets are not sent by default. You can use a program to configure this value on a connection. The recommended value setting is 300,000 (5 minutes).

KeepAliveInterval might also be of interest. All the parameters are listed here: http://support.microsoft.com/kb/314053