Yahoo web messenger can't sign in ---when i do the page goes to blank page and won't come up.

1. Go to Yahoo Mail. Open any web browser and go to the Yahoo Mail page.
2. Sign into Yahoo. Enter your Yahoo ID and password on the fields provided then click the "Sign In" button. ...
3. Access Yahoo Messenger. ...
4. Sign into Yahoo Messenger. ...
5. View the contacts list. ...
6. Delete a contact.

If you are unable to sign in to Yahoo! Web Messenger, you may see an error message such as "Website Blocked" or a notification explaining that your login credentials are incorrect.

If your computer does not meet the minimum system requirements, the browser may not be able to display the page at all.

Confirm that your computer meets the system requirements and that the Yahoo! Web Messenger website is not blocked on your network, and confirm that your password is correct to sign in and begin chatting online. No Account
To log in to Yahoo! Web Messenger, you must have a Yahoo! account.
This enables your friends to add you to their contact lists and chat with you.

It also gives you access to other services such as Yahoo! Mail.
To create an account from the Yahoo! Web Messenger page, click the "Get Started" button, and then click "Sign Up" on the following page.

Provide the requested basic information, including your name and birth date, and select your desired username and password.

Incorrect Password
When signing in to Yahoo! Web Messenger, you must provide the password that you selected when creating your Yahoo! account.

If you provide an incorrect password when signing in, Yahoo! Web Messenger displays the error message "Invalid ID or Password."
Click the "I can't access my account" link at the bottom of the sign-in screen.

On the following screen, click "I forgot my password" and then click "Next."
Follow the prompts to verify your identity and reset your Yahoo! password.

System Requirements
You may see errors if you attempt to use Yahoo! Web Messenger on a computer running an older operating system such as Windows 2000 or Millennium Edition, as Web Messenger requires Internet Explorer 6 or newer. Mozilla Firefox, Opera and Safari are also officially supported.

If you have confirmed that you are running a supported browser, navigate to the Adobe Flash Player page at adobe.com/software/flash/about.

The screen should display the message "Adobe Flash Player Successfully Installed."
Download and install Adobe Flash if you do not see this message.

Website Blocked
If you receive an error message such as "This page has been blocked" when you attempt to access the Yahoo! Web Messenger page, your network administrator has elected to block the website in the network's firewall.

Parents can also use home routers to block websites.
Ask your parents or network administrator to remove the block so you can use Yahoo! Web Messenger.
http://www.adobe.com/software/flash/about/

go to remove programs. remove and reinstall yahoo messenger. then try to sign in. if it still will not let you! change your sign in name and password.

Desktop Yahoo! messenger may be installed incorrectly or your OS has some problems. An easy way to get around this is use web messenger, like KarooLark web yahoo messenger at http://karoolark.com/#yahoo

Click on the link below:
How to install Yahoo! Messenger!

Download Yahoo Messenger

1. Proceed to the Yahoo Messenger Web site. You will click the 'Messenger' link on the Yahoo home page or you can head directly to the Messenger Web site (see Resources below).
2. Click the 'Get Started' link on the Messenger home page. This will redirect you to the download page for the latest version of Yahoo Messenger.
3. Wait a few seconds for the download to automatically begin, or press 'Click Here' in Step 1 of the Yahoo Messenger download page. This will open the dialog box that begins the download.
4. Double-click the Yahoo Messenger executable once the download completes to begin the installation process.

http://ph.messenger.yahoo.com/download/ Tips & Warnings

• Use Yahoo Messenger for voice-chat, conferencing, chat and a host of other communications options. It's even possible to send important documents to your contacts using Yahoo Messenger without having to send an email.
• If you're having trouble getting Yahoo Messenger to work, get your questions answered by visiting the Yahoo Help Web site.
• Be aware that there are some less than honorable people who use Yahoo Messenger. They are capable of crashing your services using boot programs or they will continually send you spam messages. Remember you can always choose to block, or ignore, other users so they can't continue to contact you.

Create a Yahoo Account
1. Step 1 Head to the Yahoo Web site (see Resources below) to begin the account creation process.
   
2. Step 2 Click on the 'Sign Up' link on the home page to begin the account creation process.
   
3. Step 3 Fill in all of the required fields on the page that opens. This will include your name and some additional personal information, as well as your choice for a screen name and password. If your screen name choice already exists, then you'll need to choose an alternative, or pick from the suggestions that Yahoo provides.
   
4. Step 4 Click the 'Sign Up' button again once your account is ready. This will make your Yahoo profile active.
   Download Yahoo Messenger
5. Step 1 Proceed to the Yahoo Messenger Web site. You will click the 'Messenger' link on the Yahoo home page or you can head directly to the Messenger Web site (see Resources below).
   
6. Step 2 Click the 'Get Started' link on the Messenger home page. This will redirect you to the download page for the latest version of Yahoo Messenger.
   
7. Step 3 Wait a few seconds for the download to automatically begin, or press 'Click Here' in Step 1 of the Yahoo Messenger download page. This will open the dialog box that begins the download.
   
8. Step 4 Double-click the Yahoo Messenger executable once the download completes to begin the installation process.
   

try these steps and tell me incase any issues

Create a Yahoo Account
1. Step 1 Head to the Yahoo Web site to begin the account creation process.
   
2. Step 2 Click on the 'Sign Up' link on the home page to begin the account creation process.
   
3. Step 3 Fill in all of the required fields on the page that opens. This will include your name and some additional personal information, as well as your choice for a screen name and password. If your screen name choice already exists, then you'll need to choose an alternative, or pick from the suggestions that Yahoo provides.
   
4. Step 4 Click the 'Sign Up' button again once your account is ready. This will make your Yahoo profile active.
   Download Yahoo Messenger
5. Step 1 Proceed to the Yahoo Messenger Web site. You will click the 'Messenger' link on the Yahoo home page or you can head directly to the Messenger Web site (see Resources below).
   
6. Step 2 Click the 'Get Started' link on the Messenger home page. This will redirect you to the download page for the latest version of Yahoo Messenger.
   
7. Step 3 Wait a few seconds for the download to automatically begin, or press 'Click Here' in Step 1 of the Yahoo Messenger download page. This will open the dialog box that begins the download.
   
8. Step 4 Double-click the Yahoo Messenger executable once the download completes to begin the installation process.
   

try these steps and tell me incase any issues

I would like to help you with your issue. but we have to check the following first

http://webmessenger.yahoo.com/ try log into the Web Messenger

> Step 1: Test Your Internet Connection
> Step 2: Verify Your Yahoo! ID and Password
Open Internet explorer and www.mail.yahoo.com
Check by sign in to you account
> Step 3: Test Your Access to Secure Pages
Make sure that you can access secure pages from Internet Explorer
Try to sign in to Yahoo! by going to the Yahoo! sign in page and enter the same Yahoo! ID and password you were using before.
> Step 4: Verify Credentials
Verify that the same Yahoo! ID and password you used before in the last step also works in the online version of Messenger, Yahoo! Messenger for the Web:
http://webmessenger.yahoo.com/
enter the same Yahoo! ID and password you were using before.
> Step 5: Check Connection Settings
Click the Messenger menu and select Connection Preferences.
Click Connect directly to the Internet, and then click OK.

Check by Changing the connection type to a connection via a proxy server:
Click the Messenger menu and select Connection Preferences.
Click Connect via a proxy server, then under this option, select HTTP proxy, and then click OK.


Last is Uninstall all the Yahoo Tool Bars and Yahoo applications , Yahoo Messenger, and Yahoo Updates from Program list i.e Control panel - Add/Rem Programs ..
And reinstall the Yahoo Messenger again -

Hoping the above info will be useful for you