Failed to open file for writing message

[Forex Trader]

We creaete a vb6 DLL called FFeSig, but when installed the following message appear:
"Following client components were not downloaded succesffully: 1. FFeSig.dll: Failed to open file for writing."
do you have any idea how to handle this error, or if there is something during the compile that creates the DLL as Read only?

I'll apreciate your help,
Regards