With regards to TrendMicro I still remember having to deal with an end user who had this installed and had the &quot;internet security&quot; feature enabled.<p>It intercepted the not-quite standard response header &quot;Content-Encoding: ps-bzip2&quot; to our windows client application, stripped off the header it didn&#x27;t understand but, of course, didn&#x27;t decompress the payload.<p>So our application has not seen a Content-Encoding header and thus tried to run with the presumed-non-compressed response - that went really well.<p>Since that day, our server uses a content-type header that contains the word bzip2 :(<p>The icing on the cake: The customer in question told me that their cousin is working at TrendMicro and that they are by far the best virus scanner out there and that this must clearly have been my fault.<p>I&#x27;m not surprised that they also get other stuff wrong.<p>However, I&#x27;m surprised at the level of incompetence shown here. This is a <i>security</i> product after all.