Thanks to Anvisoft.com, here are the tips on removing the annoying Delta Search from your beloved Firefox. :D
Step 1 > Uninstall Delta Search from your computer.
Follow the instruction that corresponds to your operating system to uninstall Delta Search.
• Windows XP: Go to Start> Control Panel> Add Remove programs> Look for Delta, Delta Toolbar, BrowserProtect > Click on Remove.
• Windows 7/Vista: Go to Start> Control panel> Uninstall a program/Programs and Features> Look for Delta, Delta Toolbar, BrowserProtect> click on Uninstall.
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Important notice: You may have different program related to delta search listed on your computer. Please make sure to remove them all.