After looking through the devexpress online support and following the links I finally found the solutions for running devexpress controls on IIS 7 in integrated mode. DevExpress’s response to others with this same issue was that it must be something else causing the issue, not very helpful if you ask me.
So the solution for me (and I’m guessing a majority of developers out there) was to add the attribute runAllManagedModulesForAllRequests="true" to the element modules in the web.config like below.
185 <system.webServer>
186 <validation validateIntegratedModeConfiguration="false" />
187 <modules runAllManagedModulesForAllRequests="true">
188 <remove name="ScriptModule" />
189 <add name="ScriptModule" preCondition="managedHandler" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
190 <add name="ASPxHttpHandlerModule" type="DevExpress.Web.ASPxClasses.ASPxHttpHandlerModule, DevExpress.Web.v9.3, Version=9.3.3.0, Culture=neutral, PublicKeyToken=b88d1754d700e49a" preCondition="managedHandler" />
191 </modules>
192 <handlers>
193 <remove name="WebServiceHandlerFactory-Integrated" />
194 <remove name="ScriptHandlerFactory" />
195 <remove name="ScriptHandlerFactoryAppServices" />
196 <remove name="ScriptResource" />
197 <add name="ScriptHandlerFactory" verb="*" path="*.asmx" preCondition="integratedMode" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
198 <add name="ScriptHandlerFactoryAppServices" verb="*" path="*_AppService.axd" preCondition="integratedMode" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
199 <add name="ScriptResource" preCondition="integratedMode" verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
200 </handlers>
201 <urlCompression doDynamicCompression="true" />
202 </system.webServer>