Please note that unix is case-sensitive. If you accidentally have the caps-lock key on when you type your account name or password in the login window, you will have problems, and it isn't always obvious why (just something to check on).
Your password should be at least 8 characters long, and should consist of a mixture of upper and lower case alphabetic characters and digits, and some special characters (e.g. punctuation marks - but NOT spaces or control characters). Do NOT use an easy-to-guess word which is in the dictionary, or your phone number, and do not write it down anywhere, or keep it in a file in your home directory.
Do not use a password composed of digits or letters only.
It is better not to use a digit or a special character in the first position of your new password, as some applications / Operating Systems will not accept such a password.
Do not use something you'd find in a dictionary (in any language or jargon).
Do not use names, birth dates, street or phone numbers, or any other information about yourself or someone close to you which could be readily learned or guessed. (That includes the names of places - real or fictional - and books, and even fictional characters - especially not if they are your favourites, and even more especially not if you have a web site, and have named your favourite books / music etc. on it !
Do not even use a combination of your initials followed and/or preceded by digit(s).
Do not use such combinations in reverse, either.
Do not any simple pattern of letters or numbers, such as "qwertyxx", "xyz123xx" "aBcAbC" or acronyms e.g. "BTW", "IMHO", "BangBang!" or a CS paper name.
(Hopefully we do not need to tell you not to use the word "password", or common account names like "admin" or "guest" as your password!)
Do use at least 8 characters for your password.
Do use a combination which - within the first eight positions - has a mixture of upper and/or lower case letters, digits, and at least one of the following special characters:
! % ( ) _ - = + : , . ^
You might use a word pair with punctuation inserted, a passphrase (an understandable sequence of words), or the first letter of each word in a passphrase e.g. the first line from a song (not a currently popular one or your favourite, though).
Create your password wisely.
The webpage we have provided to allow you to change your password will screen your choice of password.