Login issues have become common and complex. The first thing to know is whatever issue you have, it has nothing to do with ezccs. If you read the below in its entirety, you should be successful in working out the issue.
There are two passwords currently in use at United: (1) A Global password also known as a United password and (2) a CCS password (optional password).
The (2) CCS password (optional password) is exactly 8 characters in length and is required for certain CCS functionality. Your CCS password may look exactly like your Global password if you originally set it up that way. You may or may not see the CCS password field when you go to ccs.ual.com. It is exposed by selecting + Enter CCS Password just under the Login button.
Ezccs can be setup to use or NOT use a CCS password. This is done from the Ezccs Passwords/Options screen, where there is a selection for "Don't Use CCS Password." Selecting "Don’t Use CCS Password" from the Passwords/Options screen seems to solve most login issues. I find that many people, in fact, do not have a valid CCS password, despite the strong belief that they do.
What this means is the following: if you can log into ccs.ual.com outside of ezccs using both a CCS password and a United password (or if you you chose to Not use a CCS password and use only a United password ), then ezccs will work. This conclusion has been tested and confirmed over the hundreds of support emails I've answered on this topic.
There is, however, an ugly twist to this story. You may successfully change your passwords; in particular, your Global/United password and log in fine for a few hours, only to be locked out after those few hours have elapsed. This is almost always caused by having United mail (mail.united.com) set up on your computer or a mobile device. If you do not update each and every device that access mail.united.com with the new Global password, you will be locked out. I recommend having only one single device setup with United mail to help avoid this issue.
If you get locked out, you must call United IT support at 847-700-5800. Do not select the option to reset your password; this will only aggravate the situation. Instead, use the option that refers to lockouts. IT can unlock your password and even confirm the email issue. They may refer to it as locked out by the Exchange server.
Perform all password troubleshooting outside of Ezccs. Below are two images that will help you understand the difference between using a Not using a CCS password and using a CCS password.
Not using a CCS password:
Using a CCS password: