I am having trouble with my session data on Microsoft IIS. Here is a little background of the problem: 1) I am not personally in control of our web server. Our IT department manages it. They have IIS running on their sever and use MS SQL Server, but they have allowed me to use PHP instead of ASP. 2) I have Apache running on a local web server in our office (not the IT department). It accesses the SQL Server database remotely. I have register_global turned OFF and use the following code on each page: session_start(); session_register('logged_in'); session_register('username'); etc... Everything works PERFECTLY on my local system. 3) I have ported all of my code to the IIS server location. It accesses the database correctly but displays an error message when I try to use the session data. It does NOT post messages that the session could not be started (which is the normal sign of session data not being allowed). The message says the variable does not exist. It is as if the session is started but the variables aren't being saved. The question I have is: What concerns should I have with PHP sessions when I move from Apache to IIS? I do NOT need to know how to set up IIS to allow session data correctly (that's the job of our IT department). If this sounds like something our IT department has set up wrong, please do not feel compelled to answer this question. I just would appreciate some advice on what I may need to change in my own code so that it works with IIS instead of Apache. Thank you for your time, Matthew Perry