Problems logging in to the private area

Hi,

I am trying to solve this problem for a while now - I would be very appreciative if anyone can help.

I have my SPIP site set up on host that uses IIS web server. I have access to a PLESK control panel in which I can set up permissions of folders, new FTP users, databases and so on.

My site is hosted and working ok on that server but I got one problem - once I set up the connection with the private area for the first time it lets me in but then after a certain amount of time (and I am pretty sure it’s 24hours) if my login has timed out I can’t login again. After I enter the ’correct’ username and password the page just returns to itself emptying both fields.

In order to access the private area again I need to delete the connect.php file from the config directory and start again with the set up.

Whilst this is ok for me to do, the owners of the site are really frustrated and I need to sort this out ASAP, so any idea will be really useful.

I have read up a lot on the net for possible causes of this but with no joy so far. It seems to me some setting to the server needs to be changed as other sites work ok on other hosts that I use, but not this one... I have the gut feeling it’s to do with the wired security settings of the server, something to do with the way the main server CACHE works... is there anything I can say to the hosing provider to check/un-check for me ...

Thanks in advance for reading.

Nadia