ho acquistato un dominio da aruba.it con servio hosting windows.
utilizzo il seguente file resized.aspx per ridimensionare foto al volo.

codice:
<%@ Page Language="vb" Debug="true" %>
<%@ import namespace="system.drawing" %>
<%@ import namespace="system.drawing.imaging" %>
<%@ import namespace="system.drawing.drawing2d" %>
<%

' initialise objects

Dim strFilename as string
Dim i as System.Drawing.Image
strFilename = server.mappath(request.QueryString("img"))

i = System.Drawing.Image.FromFile(strFilename)

'Dim b as new system.drawing.bitmap(i.width, i.height, pixelformat.format24bpprgb)
Dim b as new system.drawing.bitmap(request.QueryString("w"), request.QueryString("h"), pixelformat.format24bpprgb)
dim g as graphics = graphics.fromimage(b)

' blank the image
g.clear(color.white) 



dim unit = GraphicsUnit.Pixel
dim swidth = i.width
dim sheight = i.height
dim sx = 0
dim sy = 0
dim dx = 0
dim dy = 0
dim dw = request.QueryString("w")
dim dh = request.QueryString("h")
dim rw,rh,val1,val2
rw = swidth/dw
rh = sheight/dh



if rw<rh then
val1=swidth
val2=(swidth*dh)/dw
else
val1=(sheight*dw)/dh
val2=sheight
end if


g.drawimage(i,new rectangle(dx,dy,dw,dh),new rectangle(sx,sy,val1,val2),unit)


' set the content type
response.contenttype="image/jpeg"

' send the image to the viewer
b.save(response.outputstream, imageformat.jpeg) 

' tidy up
b.dispose()

%>
in locale funziona tutto, online non mi carica le foto.
ho provato ad utilizzare anche percorsi completi con http://www ma niente.

cosa sbaglio? grazie.