Server is a Windows 2012 R2 RDS host server running various desktop apps.

We are seeing the following:

Log Name: Application
Source: ASP.NET 4.0.30319.0
Date: 02/01/2018 19:34:37
Event ID: 1309
Task Category: Web Event
Level: Warning
Keywords: Classic
User: N/A
Computer: %COMPUTERNAME%.domain.suffix
Description:
Event code: 3005
Event message: An unhandled exception has occurred.
Event time: 02/01/2018 19:34:37
Event time (UTC): 02/01/2018 19:34:37
Event ID: a3fd55700b164fbd8ddc35ab346b24bb
Event sequence: 633
Event occurrence: 5
Event detail code: 0

Application information:
Application domain: /LM/W3SVC/1/ROOT/RDWeb/Pages-1-131569377198922071
Trust level: Full
Application Virtual Path: /RDWeb/Pages
Application Path: C:\Windows\Web\RDWeb\Pages\
Machine name: %COMPUTERNAME%

Process information:
Process ID: 5380
Process name: w3wp.exe
Account name: IIS APPPOOL\RDWebAccess

Exception information:
Exception type: NullReferenceException
Exception message: Object reference not set to an instance of an object.
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.PrepareRdpFile(String& rdp_contents, String fileExtension, String ts_name, String alias, String& rdp_file_url, String& rdp_file_name, DateTime requestTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.ProcessPublishedApp(String alias, String name, String resourceFile, String fileExtension, Byte[] iconContents, UInt32 pceIconSize, Int32 resourceType, FileExtensionInfo[] fileAssociations, String[] folderNames, String securityDescriptor, ArrayList& apps, DateTime requestTime, UInt64 lastUpdateTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.GetFreshApps(DateTime requestTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.OnCacheItemRemoved(String key, Object value, CacheItemRemovedReason removedReason)
at System.Web.Caching.CacheEntry.CallCacheItemRemovedCallback(CacheItemRemovedCallback callback, CacheItemRemovedReason reason)



Request information:
Request URL:
Request path:
User host address:
User:
Is authenticated: False
Authentication Type:
Thread account name: IIS APPPOOL\RDWebAccess

Thread information:
Thread ID: 815
Thread account name: IIS APPPOOL\RDWebAccess
Is impersonating: False
Stack trace: at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.PrepareRdpFile(String& rdp_contents, String fileExtension, String ts_name, String alias, String& rdp_file_url, String& rdp_file_name, DateTime requestTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.ProcessPublishedApp(String alias, String name, String resourceFile, String fileExtension, Byte[] iconContents, UInt32 pceIconSize, Int32 resourceType, FileExtensionInfo[] fileAssociations, String[] folderNames, String securityDescriptor, ArrayList& apps, DateTime requestTime, UInt64 lastUpdateTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.GetFreshApps(DateTime requestTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.OnCacheItemRemoved(String key, Object value, CacheItemRemovedReason removedReason)
at System.Web.Caching.CacheEntry.CallCacheItemRemovedCallback(CacheItemRemovedCallback callback, CacheItemRemovedReason reason)


Custom event details:

Event Xml:



1309
3
3
0x80000000000000

63443
Application
%COMPUTERNAME%.domain.suffix



3005
An unhandled exception has occurred.
02/01/2018 19:34:37
02/01/2018 19:34:37
a3fd55700b164fbd8ddc35ab346b24bb
633
5
0
/LM/W3SVC/1/ROOT/RDWeb/Pages-1-131569377198922071
Full
/RDWeb/Pages
C:\Windows\Web\RDWeb\Pages\
%COMPUTERNAME%


5380
w3wp.exe
IIS APPPOOL\RDWebAccess
NullReferenceException
Object reference not set to an instance of an object.
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.PrepareRdpFile(String& rdp_contents, String fileExtension, String ts_name, String alias, String& rdp_file_url, String& rdp_file_name, DateTime requestTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.ProcessPublishedApp(String alias, String name, String resourceFile, String fileExtension, Byte[] iconContents, UInt32 pceIconSize, Int32 resourceType, FileExtensionInfo[] fileAssociations, String[] folderNames, String securityDescriptor, ArrayList& apps, DateTime requestTime, UInt64 lastUpdateTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.GetFreshApps(DateTime requestTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.OnCacheItemRemoved(String key, Object value, CacheItemRemovedReason removedReason)
at System.Web.Caching.CacheEntry.CallCacheItemRemovedCallback(CacheItemRemovedCallback callback, CacheItemRemovedReason reason)










False


IIS APPPOOL\RDWebAccess
815
IIS APPPOOL\RDWebAccess
False
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.PrepareRdpFile(String& rdp_contents, String fileExtension, String ts_name, String alias, String& rdp_file_url, String& rdp_file_name, DateTime requestTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.ProcessPublishedApp(String alias, String name, String resourceFile, String fileExtension, Byte[] iconContents, UInt32 pceIconSize, Int32 resourceType, FileExtensionInfo[] fileAssociations, String[] folderNames, String securityDescriptor, ArrayList& apps, DateTime requestTime, UInt64 lastUpdateTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.GetFreshApps(DateTime requestTime)
at Microsoft.TerminalServices.Publishing.Portal.RWSCPUBAccessor.OnCacheItemRemoved(String key, Object value, CacheItemRemovedReason removedReason)
at System.Web.Caching.CacheEntry.CallCacheItemRemovedCallback(CacheItemRemovedCallback callback, CacheItemRemovedReason reason)

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