Site slowed down due graphical content

If your Sharepoint site had slowed down considerably since you added several images to it, that's all because IE was checking every image to see if it had changed before displaying it.

A quick change to the IIS Application can improve the performance of the Site by simply adding a cache-control directive to the response headers...

cache-control: max-age=3600, no-check

Another way to do it is to use the BlobCache which can be configured in the web.config. It also adds the max-age to the response headers:

#BlobCache location="D:\blobCache" path="\.(gifjpgpngcssjs)$" maxSize="1" max-age="3600" enabled="true" /#

Session state can only be used when enableSessionState is set to true

It's likely that some of us got this "Session state can only be used when enableSessionState is set to true..." Sharepoint Error while intending to extend a WSS HTTP site collection to HTTPS.

I have SSL enabled for my port 80 site but still get that message... what's wrong??

Well,

1- Make sure your WSS web site has been properly extended to SSL (this creates an https mirror site using another port). The content data is not replicated but shared among both sites (HTTP and HTTPS)

2a- Add enableSessionState="true" ... to the web.config file pages tag of the HTTPS site.

2b- Another option is just to copy/overwrite the HTTPS web.config file with the one at port 80 commonly located at \Inetpub\wwwroot\wss\VirtualDirectories\80