Code:

T_ID=request.querystring("log_id")
if len(T_ID)=0 or not isnumeric(T_ID) then T_ID=request.querystring("TOPIC_ID")
if len(T_ID)>0 and isnumeric(T_ID) then
'	response.write	T_ID
	response.redirect "grarticles.asp?log_id="&T_ID
else
	response.write	"Error"
end if

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Sure it's a 404 & not a 500? Got Linkage? Deleted the "dim T_ID" line above as it's not really necessary and may be the cause of a 500 error.
<

Go it, didn't realise you were placing this code on the page you were redirecting to so what I gave you was creating an infinite loop.
Here's the code you need:

Code:

T_ID=request.querystring("log_id")
if len(T_ID)=0 or not isnumeric(T_ID) then T_ID=request.querystring("TOPIC_ID")
if len(T_ID)>0 and isnumeric(T_ID) then
	response.write	"Code"
else
	response.write	"Error"
end if

There's actually no need for the redirect, just be sure to reference T_ID everywhere within your code. The "Code" I've highlighted in green above is where you place the code for your page, the "Error" is whatever error you want to present to members if T_ID is not valid, i.e., it's empty or doesn't have a numeric value.
<

I did another workaround =)

On topic.asp I added this:

strSQL7 = "SELECT FORUM_ID FROM FORUM_TOPICS WHERE TOPIC_ID = " & cLng(Request.Querystring("TOPIC_ID")) & ""
set ARTrs = Server.CreateObject("ADODB.Recordset")
ARTrs.open strSQL7, strConnString
if not ARTrs.EOF then
if ARTrs("FORUM_ID") = 85 then
Response.Redirect("grarticles.asp?log_id=" & cLng(Request.Querystring("TOPIC_ID")) & "")
end if
end if
ARTrs.close

To check if the topic is supposed to be an article, then redirect to the article mod.
This soled my problem, but maybe not in the best way =)

Thanks Shaggy for your time! <

Okay, it's just me being a n00b, sorry =)
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