Is there any reason why this would be happening?

It get's the job done. But it's picking it up as a virus for "
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On computer as of
12/7/2010 at 3:06:37 PM
Last Used:
12/7/2010 at 3:08:16 PM
Startup Item: No
Launched: Yes
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Very Few Users
Fewer than 10 users in the Norton Community have used this file.
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High
This file risk is high.
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Threat Details
SONAR Protection monitors for suspicious program activity on your computer.
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Origin

Downloaded from Not Available
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URL Not Available
UNTESTED

Source
powder-sse2.exe
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File Actions
File: c:\users\chris\desktop\powdertoy 43\powder-sse2.exe
Removed
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File Thumbprint:
Not Available
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Thanks plypencil.