In general, many problems with connecting to or using MyUH can be fixed by these things:

There are three main causes for this error message:
You have attempted to login with the incorrect password too many times.
MyUH will automatically disable your account for a short time after too many login failures (the more failures, the longer the time the account is disabled). If your account is disabled for this reason, you should wait a few minutes and then try again. If this does not fix the problem, or if you need to login immediately, you should contact the ITS Help Desk to get your account reenabled.
If you are not a current faculty, staff, or student of the University and your grace period to enroll in 'Ohana online services has ended, you will no longer be able to login to MyUH.
MyUH is only available for current faculty, staff, and students. Former students who have enrolled in 'Ohana online services can check their unofficial transcripts by going to STAR. Former students who have not enrolled in 'Ohana online services will need to contact their campus' Admissions and Records office to request an official transcript. Former faculty, staff, or students trying to check email can do so through UH WebMail.
You were previously a faculty, staff, or student of the University and have recently rejoined the UH Community as a faculty, staff, or student.
MyUH access is removed from a former faculty, staff, or student once their UH Username grace period has ended. When rejoining the UH Community, it takes five to ten minutes to restore MyUH access (during peak usage times, such as registration periods, this could be up to a couple hours). Try waiting five to ten minutes to access MyUH. If, after waiting, you still get this error, contact the ITS Help Desk to get your MyUH access restored.
Try following the steps in Ask Us article 1107 to correct this problem.
Please check which web browser you are using. The AOL web browser is known to have this problem, but it could also appear in other unsupported browsers.
The recommended browsers for MyUH are
To check which web browser you are using:
PC: Go to the Help menu and select About...
Mac: Go to the menu to the direct right of the Apple menu, and select About...
Please make sure that your browser's cookie setting is configured to accept cookies correctly. Cookie settings
Toolbars that are installed in your web browser may also have cookie settings. If you have a toolbar (e.g. Google toobar, Yahoo toolbar) please check their options and make sure it's configured to allow cookies for myuh.hawaii.edu.
Security software such as McAfee or Symantec may also have cookie settings. Please check the options in your security software and make sure it's configured to allow cookies for myuh.hawaii.edu.
If all cookie settings are OK, make sure that myuh.hawaii.edu is a trusted site for popups. Popup settings
Check your MyUH Portal time out setting, and increase it to the maximum:
Clear your cache, then go to http://myuh.hawaii.edu and see if you now get the login page.
You can try these things:
This page requires access through port 8888. If you are trying to access the page from a non-UH network such as a commercial business, they might have a firewall implemented on their network and not allow access through port 8888. You should check with your company's IT if there is a firewall in place.
If you are at home, make sure your software or hardware firewall (many routers and wireless access points also have a built in firewall) allows access through port 8888.
You can try these things: