来看个URL重写规则，哪里没有正确啊？时不时的就抛出404资源找不到的异常。另外追问下，正则表达式里面 . 号需不需要写成 \. ?
<!--Url   重写规则-->
<configSections>
<!--   The   <configSections>   element   must   contain   a   <section>   tag   for   the   <RewriterConfig>   section   element.
The   type   of   the   section   handler   is   RewriterConfigSerializerSectionHandler,   which   is   responsible   for
deserializing   the   <RewriterConfig>   section   element   into   a   RewriterConfig   instance...   -->
<section   name= "RewriterConfig "   type= "URLRewriter.Config.RewriterConfigSerializerSectionHandler,   URLRewriter "/>
</configSections>
<RewriterConfig>
<Rules>
<RewriterRule>
<LookFor> ~/(\w*)/archive/(\w*).aspx </LookFor>
<SendTo> ~/$1/archive.aspx?id=$2 </SendTo>
</RewriterRule>
<RewriterRule>
<LookFor> ~/(\w*)/categories/(\w*).aspx </LookFor>
<SendTo> ~/$1/default.aspx?id=$2 </SendTo>
</RewriterRule>
<RewriterRule>
<LookFor> ~/(\w*)/categories/(\d*)-(\d*).aspx </LookFor>
<SendTo> ~/$1/default.aspx?id=$2&amp;page=$3 </SendTo>
</RewriterRule>
<RewriterRule>
<LookFor> ~/(\w*)/default-(\d*).aspx </LookFor>
<SendTo> ~/$1/default.aspx?page=$2 </SendTo>
</RewriterRule>
</Rules>
</RewriterConfig>

------解决方案--------------------
正则表达式里面 . 号需不需要写成 \.?
---->
.匹配除换行符以外的任意字符
www\.unibetter\.com匹配www.unibetter.com
------解决方案--------------------
看楼主的意思，应该要加 "\ "