Probably some setting in your mouse driver if that is not the standard Microsoft one in normal mode.
Kees
Hello. =) I am using a dell optiplex 755, windows xp SP3. I don't have the problem whenever I enter safe mode. My mouse always performs a double click instead of a single click; it isn't a random occurrence. I have run Malware Bytes several times, and my computer always comes up clean. I appreciate any help provided, thank you.

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