DOCUMENT:Q182712 02-MAY-1999 [iis] TITLE :Err Msg: "Unable to Connect to " Over SSL Connection PRODUCT :Internet Information Server PROD/VER:WINNT: 3.0 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Internet Information Server 3.0 ------------------------------------------------------------------------------- SYMPTOMS ======== On a Web site with a large number of concurrent users using Secure Sockets Layer (SSL), the client may randomly receive the following error message: Unable to connect to '' a connection with the server could not be established. Refreshing the page can recover the session. CAUSE ===== The more complex the page, the longer it takes to download the page; therefore, the fewer people who can enter the site at one time. If you have a site with complex pages, you will encounter this problem with only a small number of concurrent users more frequently than will a site with simpler pages. This problem arises because each individual object on a page creates a separate session to download this object to the client. By default, the SSL component has only sufficient cache to maintain 100 sessions. This limitation is associated with the schannel component (Schannel.dll), used for SSL/PCT. WORKAROUND ========== WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. For information about how to edit the registry, view the "Changing Keys And Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it. To increase the size of the SSL server cache, modify the following registry entry: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL Value Name: ServerCache Data Type: REG_DWORD Data: 1000 (Default = 100) ====================================================================== Keywords : Technology : kbiisSearch kbiis300 Version : WINNT: 3.0 Hardware : ALPHA PPC x86 Issue type : kbprb ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 1999.