Explorer Restricted site problem

[Doz]

I hope someone can help!
I'm a player of an online game & one of my fellow players is a programmer and has developed an add-on program which greatly speeds up certain aspects of the game. I know this program is not harmful and works as others in the game use it. However when i try to open it in Explorer it marks it as a restricted site, yet it is not listed in the restricted sites window. I have tried to enter it into the 'trusted sites' box but it says 'you have come up with an invalid wilcard sequence' even though I cannot see any invalid sequences in the address (it's: C:\Documents and Settings\myname\Desktop\Sleuth2-2-aug-2008\Sleuth2\SleuthCase.html)I have tried altering security settings but nothing seems to work.
I hope someone has some ideas. Many thanks in advance.

[Carbon Dudeoxide]

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[Doz]

Custom built computer, Windows XP, latest version of Explorer. No other problems experienced with either hardware or software.
Have had a friend look at the problem some time ago who is a bit of a computer whizz - and he couldn't work it out either.
I really hope someone can help...

[patio]

Where is the addon so we can test it ? ?
What exactly does it do ? ?
What games ? ?