Have you tried searching in your Web.config for CrystalImageHandler (in the httpHandlers section)? I had to add a line to display my inline images:
<add verb="GET" path="CrystalImageHandler.aspx" type="CrystalDecisions.Web.CrystalImageHandler, CrystalDecisions.Web, Version=10.5.3700.0, Culture=neutral, PublicKeyToken=692FBEA5521E1304"/>
source share