Hi,

I have installed the Application Catalog web service point and Application Catalog website point with default settings. I have configured all the client settings and IIS default website settings following every available document on technet. 

But i get an error "Cannot connect to the Application server", no matter what. 

In the ServicePortalWebSite.log, every time i click on the URL: I get this following error:

[1, PID:12416][08/31/2015 16:34:55] :AppCacheableBase - configured writable app directory set to: D:\Program Files\SMS_CCM\CMApplicationCatalog\Content\Images\AppIcons
[1, PID:12416][08/31/2015 16:34:55] :ASP.NET application cache will NOT be used (either cache dir not found, asp.net cache is not set, or cache setting in web.config is <= 0
[11, PID:12416][08/31/2015 16:34:55] :Passed in language: en-US
[11, PID:12416][08/31/2015 16:34:55] :Language resolved to: en-US
[11, PID:12416][08/31/2015 16:34:55] :SoftwareCatalog website - requested resource: ~/, api-version: ""
[11, PID:12416][08/31/2015 16:34:55] :Passed in language: en-US
[11, PID:12416][08/31/2015 16:34:55] :Language resolved to: en-US
[11, PID:12416][08/31/2015 16:34:55] :SoftwareCatalog website - requested resource: ~/default.aspx, api-version: ""
[11, PID:12416][08/31/2015 16:34:55] :No current build version found so will try to get one
[11, PID:12416][08/31/2015 16:34:55] :Got 5.0.8239.1000 build version 
[11, PID:12416][08/31/2015 16:34:56] :Passed in language: en-US
[11, PID:12416][08/31/2015 16:34:56] :Language resolved to: en-US
[11, PID:12416][08/31/2015 16:34:56] :SoftwareCatalog website - requested resource: ~/ApplicationViewService.asmx, api-version: "1.0"
[12, PID:12416][08/31/2015 16:34:56] :Passed in language: en-US
[12, PID:12416][08/31/2015 16:34:56] :Language resolved to: en-US
[12, PID:12416][08/31/2015 16:34:56] :SoftwareCatalog website - requested resource: ~/ApplicationViewService.asmx, api-version: "1.0"
[11, PID:12416][08/31/2015 16:34:56] :System.NullReferenceException: Object reference not set to an instance of an object.
   at Microsoft.ConfigurationManager.SoftwareCatalog.Website.PortalClasses.PortalUser.InitializeUserAndGroups(IIdentity userId)
   at Microsoft.ConfigurationManager.SoftwareCatalog.Website.PortalClasses.PortalUser..ctor(IIdentity userId, Int32 useLocale)
   at Microsoft.ConfigurationManager.SoftwareCatalog.Website.ApplicationViewService.GetMobileApplicationValuesForProperty(ApplicationProperty propertyName, Platforms platformFilter, String reserved)
   at Microsoft.ConfigurationManager.SoftwareCatalog.Website.ApplicationViewService.GetApplicationValuesForProperty(ApplicationProperty propertyName, String reserved)

I have been stuck with this problem since 3 weeks. Please help me with this.

Thanks

the log which you posted is generic ,should also check other logs to find the issue.What does your site system says about application catalog thread ?

ServicePortalWebSite.log --->this log tells you the activity of the Application Catalog website.
check ServicePortalWebService.log--> Records the activity of the Application Catalog web service and awebsvcMSI.log for installation of Application Catalog web service point and portlwebMSI.log for application Catalog website role installation. You may find some clue about the error from above logs.