Critical Issue trying to login

Hello - I have something major happening and I don't understand what happened. As a side note I didn't play with any settings regarding Dolphin.

For the past few days I have received messages from members of my community telling me they are not able to access my site. They asked for the password to be re-sent and they tried that password... They get: Error! Your username or password was incorrect. Please try again.

The CRITICAL PART... when I go as an admin... change the password to 12345 (get successful result). I try to login with their user name and 12345 and I'm Getting: Error! Your username or password was incorrect. Please try again.

Can anyone help me please... this is very important issue :(

well .. this well take a bit of work to check it out so .. here is the steps

go to phpmyadmin and open the profiles table from the database .. right there you can see the users and there hashed passwords and slats of those passwords ..

now see what is the last id you have (lets say it was 100 )

and then in the sql section insert this quirey

INSERT INTO `profiles` (`ID`, `NickName`, `Email`, `Password`, `Salt`, `Status`, `Role`, `Couple`, `Sex`, `LookingFor`, `Headline`, `DescriptionMe`, `Country`, `City`, `DateOfBirth`, `Featured`, `DateReg`, `DateLastEdit`, `DateLastLogin`, `DateLastNav`, `aff_num`, `Tags`, `zip`, `EmailNotify`, `LangID`, `UpdateMatch`, `Views`, `Rate`, `RateCount`, `CommentsCount`, `PrivacyDefaultGroup`, `allow_view_to`, `UserStatus`, `UserStatusMessage`, `UserStatusMessageWhen`, `Avatar`, `Height`, `Weight`, `Income`, `Occupation`, `Religion`, `Education`, `RelationshipStatus`, `Hobbies`, `Interests`, `Ethnicity`, `FavoriteSites`, `FavoriteMusic`, `FavoriteFilms`, `FavoriteBooks`, `FirstName`, `LastName`, `FacebookProfile`) VALUES
(101, 'admin', 'your@email.here', '04673fb3da3932c6078ca873564691667631fc1d', 'YmRjM2Uz', 'Active', 3, 0, '', '', '', '', '', '', '0000-00-00', 0, '2011-08-01 12:48:03', '0000-00-00 00:00:00', '2011-08-10 05:26:27', '2011-08-10 05:26:27', 0, '', '', 1, 0, 1, 0, 0, 0, 0, 3, 3, 'online', '', 0, 1, '', '', '', '', '', '', NULL, '', '', '', '', '', '', '', '', '', '');

now i have put an id of 101 becouse the last id is 100 ( iguess you get what i mean )

admin is the user name (change it to what ever you like).

the password for this user will be admin as well

so after you add this user though the phpmyadmin try to login and tell us what happens