State Management :: Deleting Folder And Session State Mode?

I write a simple web site in asp.net. In one page i want to delete a folder of web root. When i delete it folder, the all session in project is changed to null. I write a post in this forum. Here is the adress of it post: ([URL]) Some pepole answer me to change the session state mode to StateServer. In default the session state mode is Inproc, and i changed the session state mode to stateServer.but when i changed the session to stateserver this error is appear in application eventlog after two day and my web site dont working in iis. This error is like this:

Event Type:
Warning
Event Source:
ASP.NET 2.0.50727.0
Event Category:
Web Event
Event ID:
1310
Date:
3/12/2011
Time:
1:27:55 PM
User:
N/A
Computer:
WIN2003-00A346F
Description:
Event code: 3009
Event message: Unable to make the session state request to the session state server. Details: last phase='Sending request to the state
server', error code=0x80072749, size of outgoing data=0
Event time: 3/12/2011 1:27:55 PM
Event time (UTC): 3/12/2011 8:57:55 AM
Event ID: a5c8bfd16f74429e820989e8ce8082d0
Event sequence: 10
Event occurrence: 1
Event detail code: 50016
Application information:
Application domain: /LM/W3SVC/1547208020/Root-1-129443938731955000
Trust level: Full
Application Virtual Path: /
Application Path: C:InetpubwwwrootClishareClishare
Machine name: WIN2003-00A346F
Process information:
Process ID: 1276
Process name: aspnet_wp.exe
Account name: WIN2003-00A346FASPNET
Exception information:
Exception type: HttpException

Exception message: Unable to make the session state request to the session state server. Please ensure that the ASP.NET State service is started and that the client and server ports are the same. If the server is on a remote machine, please ensure that it accepts remote requests by checking the value of HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesaspnet_stateParametersAllowRemoteConnection. If the server is on the local machine, and if the before mentioned registry value does not exist or is set to 0, then the state server connection string must use either 'localhost' or '127.0.0.1' as the server name.

Request information:
Request URL: [URL]
Request path: /main/home.aspx
User host address: 64.79.69.155
User:
Is authenticated: False
Authentication Type:
Thread account name: WIN2003-00A346FASPNET
Thread information:
Thread ID: 1
Thread account name: WIN2003-00A346FASPNET
Is impersonating: False

Stack trace: Custom event details: For more information, see Help and Support Center at [URL]. When i reset ASP.NET State service, the problem is fixed, but after one or two days, this problem apears again. What's the problem and how can i fix it? And how can i delete a folder in asp.net without the session is lost?