Ruth,
I am not a phpbb expert at all but have found this. Hopefully it will assist you in ask the forum hosting company the relevant fix.
Cookies are small text files created when you visit a web site that includes a command to create them. The file contain pieces of information stored in a folder on your computer ready to be accessed again in the future. They allow information to be stored that is specific to you which allows the web site the retrieve that information next time you visit the site. For example, cookies are used to save personalized settings from web sites, to store shopping basket content on some online shops and to store information about the number of times the visitor has visited a web site, to name a few. It is important to note that only the web site that set the cookie can have access to it and that a web site cannot access cookies already stored by other sites.
Cookies are used within phpBB2 for a number of things, the main one being the automatic login feature. When you click the ‘Log Me In Automatically’ box available on most forums, phpBB will set a cookie with your information in. Next time you visit the forums, you will be automatically logged in!
There are many topics on the phpBB support forums regarding the inability to keep users logged in or the cookies not working properly. Here is a guide to what each option is on your configuration screen:
Cookie Domain: This is default on most forums as your domain name without the http:// part. This tells the cookie which site set it and allows that site to retrieve it. This is the most commonly incorrectly set option and if set incorrectly, will lead to the inability to stay logged in.
Cookie Name: This is set as default as phpbb2mysql and is just the name that the cookie is given when being stored. It doesn't matter what this is set as but changing it will cause all the cookies to be needed to be added again. It is advised to give the cookie a name. If you are running multiple forums on the same server, it is advisable to have a different cookie name for each forum.
Cookie Path: This is where the cookie is directed to and is defaulted as / but this will depend on your forum location in your site directory. A common mistake here to put the URL (i.e.
http://www.yoursite.com) as the path which is incorrect.
Cookie Secure: If you are running SSL on your site with the forums loaded with it, then enable this option to make the cookies secure.
Session Length: This sets how the long each user session lasts – if the user does not do anything for the number of seconds set here, they are logged out. The default of 3600 is usually fine for most boards.
• The Log Me In Automatically Box is not working:
This is because you have not set up the cookie domain or path correctly. Read the above information and double check your setup.