La "Vista en vivo" me aparece en blanco

You are not providing enough information to give us a clue of what is happening. So, here starts a guessing game.

Here are a few potential solutions:

1. Refresh Live View – Sometimes, simply turning Live View off and back on again can resolve the issue.
2. Check .htaccess Files – Some users found that deleting .htaccess files in their site folders fixed the problem.
3. Validate Your Code – A missing end tag (like <title>) can cause Dreamweaver’s Live View to go blank, even if browsers display the page correctly.
4. Check Server Settings – If you're using a local server, ensure that your settings (server name, connection type, and web URL) are correctly configured.
5. Clear Cache – If Live View won’t refresh, renaming or deleting the cache folder in Dreamweaver’s configuration files might help.

If none of these work, you might want to check out Adobe’s official troubleshooting guide here.