If you know you have a valid web site (and forums) account here but can't log in to the web site there are a couple things you should do.
Note: Some users have experienced inability to login when in fact they ARE logged in...sometimes 5 or 6 times simultaneously! If the site returns no errors but keeps prompting you to login then you ALMOST CERTAINLY need to clear you cookes and browser cache... see items 1 and 2 below.
1) Most login problems are due to bad browser "cookies". Cookies are stored on your computer, not the website, and they hold your login inforomation (and other data) so that you don't have to repeat it each time you visit. If you have logged in before and can't get back in now you almost certainly have a corrupted cookie. Look in your browser menu and find the option to clear your cookies. After having done that please try to log in to the web site again.
2) Occassionally your browser cache (stored images of web pages you visit) becomes corrupted. There have been cases where a member logs in successfully but is shown a page that indicates they have not logged in. This is usually due to the browser having cached a login failure page that it displays in place of the web site itself. Clear your browser cache and try again.
3) If you find the username/password block doesn't appear to accept your credentials, try logging in at http://www.IowaGeocachers.org/?q=user.
4) Visit the web site and click on the "Request new password" link there. Follow the prompts to supply necessary information, then look for an e-mail from the site with additional information.
5) If you're using Internet Explorer (any version) then consider UPGRADING to Firefox. IE is a pain in the a$$ of nearly every webmaster I know, and there are simply things that it can't/won't do PROPERLY. For every hour I spend working on the web site I could easily spend another 4 hours making sure it works in Internet Explorer... and I have neither the time nor the patience to do that.
6) If all else fails, send an e-mail to me, firstname.lastname@example.org, and include details of your login attempts... username, password (optional), any errors or warnings that you have recieved. Screen shots of anything you see are extremely helpful... I don't see the same screens/site that you do!