Server.MapPath() 错误 'ASP 0173 : 80004005'

无效 Path 字符

/KS_Cls/Kesion.Thumbs.asp，行 192

为 MapPath 方法指定的 Path 参数中包含一个无效字符。

我找到/KS_Cls/Kesion.Thumbs.asp文件.

185 End If
186 Set objImage = KS.InitialObject("Persits.Jpeg")
187 Set objMark = KS.InitialObject("Persits.Jpeg")
188 objImage.Open FileName
189 If objImage.OriginalWidth < MarkWidth Or objImage.OriginalHeight < MarkHeight Then
190 Exit Function
191 End If
192 objMark.Open Server.MapPath(MarkPicture)
193 

194 'objImage.Canvas.DrawImage 0,objImage.OriginalHeight/2-33,objMark,0.6,&HFFFFFF
195 

196 GetPostion CInt(MarkPosition), x, y, objImage.OriginalWidth, objImage.OriginalHeight, MarkWidth, MarkHeight
197 If MarkTranspColor <> "" Then
198 objImage.Canvas.DrawImage x, y, objMark, MarkOpacity, MarkTranspColor
199 'objImage.Canvas.DrawImage x, y, objMark, MarkOpacity,&HFFFFFF
200 Else
201 objImage.DrawImage x, y, objMark, MarkOpacity
202 End If

需要怎么改Kesion.Thumbs.asp这文件，或者后台需要怎么设置才能把这错误排除！