I will say up front, I am not a super technical user.

I have a web site that we installed (hosted by GoDaddy).  It was installed in 2005 and since then we really haven't changed it much at all other than posting information for the users.  Suddenly in the past few weeks, we started having login issues.  At first it was intermittent, now nobody (there are about 150 users) can login.  I can't login with my normal ID or the ADMIN id - I also have test ID's that I created in the past that I tried.  I have used password reminder to verify my password and I am using the correct password.    I am pasting the error message everyone gets when the try to login.

I have checked with GoDaddy, but they say its a DNN issue so they can't help (even though it was a application installed through their application installs). 

Can anyone give me some ideas of what might help?

Login

Login Failed, remember that Passwords are case sensitive User Name: Enter your User name here. In most cases this will be your email address. Password: Enter your Password Remember Login

On version 4.0.2.

I hadn't changed anything prior to the issues, other than adding/changing content in one of the txt/html modules for information for users of the site, but was able to login after that.