List of Silverlight Error Codes with Explanations:

The below list contains Silverlight Error Codes which can be used for user friendly messaging: 


1001 
AG_E_UNKNOWN_ERROR 

2000 
Document is not well-formed XAML. 

2001 
DTDs are not allowed. 

2002 
Entity references to named entities other than lt, gt, amp, apos, and quot are not allowed. 

2003 
Entity definitions are not allowed. 

2004 
Only UTF-8 and UTF-16 encodings are supported. 

2005 
Unknown namespace %0. 

2007 
Unknown element: %0. 

2008 
Cannot specify the value multiple times for properties. 

2009 
Cannot specify content for %0 and set its %1 property at the same time. 

2010 
%0 does not support %1 as content. 

2011 
%0 does not support text content. 

2012 
Unknown attribute %0 on element %1. 

2013 
Attribute %0 value is out of range. 

2014 
The attribute %0 is read only and cannot be set. 

2015 
Cannot declare custom namespaces in JavaScript. 

2016 
Cannot specify both Name and x:Name attributes. 

2017 
Null is not a legal value for attribute %0. 

2018 
The element %0 does not support attributes. 

2019 
Xaml may not use base type names, use %0 instead. 

2020 
Invalid Property: %0. 

2021 
Invalid enum value. 

2022 
Unknown Color: %0. 

2023 
%0 is not an event. 

2024 
Invalid attribute value %0 for property %1. 

2025 
AG_E_PARSER_ATTRIBUTE 

2027 
AG_E_PARSER_ELEMENT 

2028 
The name already exists in the tree: %0. 

2030 
Property element %0 cannot be used inside another property element. 

2031 
The property element %0 must appear before other content. 

2033 
Cannot specify the value multiple times for property: %0. 

2034 
Elements in a ResourceDictionary must have x:Key or x:Name attribute. 

2035 
The element is not valid in the given namespace. 

2036 
XamlReader.Load() does not accept event handlers. 

2100 
AG_E_INIT_CALLBACK 

2101 
Failed to initialize the application's root visual 

2102 
Invalid source file specified on Silverlight plug-in. Expected Uri for application file 

2103 
Invalid or malformed application: Check manifest 

2104 
Could not download the Silverlight application. Check web server settings 

2105 
Failed to load pre-requisites for the application 

2106 
Failed to load the application. It was built with an obsolete version of Silverlight 

2107 
Splash screen file needs to be on the same domain as the application 

2108 
Failed to download the splash screen 

2150 
Failed to load a platform extension. Possibly corrupt or non-existent file: %0 

2152 
Failed to download a platform extension: %0 

2153 
Failed to load a platform extension. Possibly corrupt or invalid file: %0 

2201 
AG_E_RUNTIME_INVALID_CALL 

2202 
AG_E_RUNTIME_FINDNAME 

2203 
AG_E_RUNTIME_SETVALUE 

2204 
AG_E_RUNTIME_GETVALUE 

2205 
AG_E_RUNTIME_ADDEVENT 

2206 
AG_E_RUNTIME_DELEVENT 

2207 
AG_E_RUNTIME_METHOD 

2208 
AG_E_RUNTIME_GETHOST 

2209 
AG_E_RUNTIME_GETPARENT 

2210 
AG_E_INVALID_ARGUMENT 

2211 
AG_E_RUNTIME_HTML_ACCESS_RESTRICTED 

2212 
Animation target not specified. 

2213 
Cannot resolve TargetName %0. 

2214 
Cannot resolve TargetProperty %0 on specified object. 

2215 
%0 cannot be used to animate property %1 due to incompatible type. 

2216 
Multiple animations in the same containing Storyboard cannot target the same property on a single element. 

2217 
KeyTime property on KeyFrame object must be set to a non-negative TimeSpan value. 

2218 
Operation is not valid on an active Animation or Storyboard. Root Storyboard must be stopped first. 

2219 
Operation is not allowed on a non-root Storyboard. 

2220 
Cannot determine Storyboard Duration. 

2221 
Shader file %0 not found. 

2222 
Invalid shader. 

2250 
AG_E_RUNTIME_MANAGED_UNKNOWN_ERROR 

2251 
AG_E_RUNTIME_MANAGED_ACTIVATION 

2252 
AG_E_RUNTIME_MANAGED_ASSEMBLY_DOWNLOAD 

2253 
AG_E_RUNTIME_MANAGED_ASSEMBLY_LOAD 

2254 
AG_E_PARSER_UNKNOWN_TYPE 

2255 
AG_E_PARSER_BAD_TYPE 

2256 
AG_E_PARSER_BAD_NATIVE_TYPE 

2257 
AG_E_PARSER_CREATE_OBJECT_FAILED 

2258 
AG_E_PARSER_PROPERTY_NOT_FOUND 

2259 
AG_E_PARSER_BAD_PROPERTY_TYPE 

2260 
AG_E_PARSER_BAD_PROPERTY_VALUE 

2261 
AG_E_PARSER_ROOT_NOT_CUSTOM 

2262 
AG_E_PARSER_NAMESPACE_NOT_SUPPORTED 

2263 
AG_E_PARSER_MISSING_DEFAULT_NAMESPACE 

2264 
AG_E_PARSER_INVALID_XMLNS 

2265 
AG_E_PARSER_INVALID_CLASS 

2266 
AG_E_RUNTIME_MANAGED_BAD_DLR_SCRIPT 

2267 
AG_E_PARSER_INVALID_XCODE_TAG 

2268 
AG_E_PARSER_ELEMENT_IGNORED 

2269 
Elements in a ResourceDictionary must not set both x:Name and x:Key, or x:Key twice 

2270 
Attribute x:Key set on an invalid object, only objects in a ResourceDictionary can have x:Key 

2271 
Improper syntax for Static Resource (ie: {StaticResource Key}) 

2272 
Cannot find a Resource with the Name/Key %0 

2273 
Elements in the same ResourceDictionary cannot have the same x:Key 

2274 
AG_E_RUNTIME_MANAGED_ASSEMBLY_NOT_FOUND 

2275 
Invalid characters in Source Uri. 

3000 
AG_E_UNABLE_TO_PLAY 

3001 
AG_E_INVALID_FILE_FORMAT 

3002 
AG_E_NOT_FOUND 

3003 
AG_E_MEDIA_DISCONNECTED 

3004 
Invalid ASX element 

3005 
Invalid ASX attribute 

3006 
Unsupported ASX element 

3007 
Unsupported ASX attribute 

3008 
ASX parse error 

4000 
AG_E_ABORT_FAILED 

4001 
AG_E_NETWORK_ERROR 

4002 
AG_E_ACCESS_DENIED 

4003 
AG_E_INVALID_POLICY 

4004 
AG_E_MANAGED_EXCEPTION 

4005 
XamlReader.Load() does not support x:Class. 

4006 
Only the root element can have an x:Class attribute. 

4007 
The root element must be , not a subclass of UserControl. 

4008 
Layout cycle detected. Layout could not complete. 

4009 
Element is already the child of another element. 

4010 
The ItemsControl.ItemsPanelTemplate must have a derivative of Panel as the root element. 

4011 
Setting the Template property on a UserControl is not supported. 

4012 
Cannot explicitly modify Children collection of Panel used as ItemsPanel for ItemsControl. ItemsControl generates child elements for Panel. 

4013 
Cycle detected in merged resource dictionaries 

4014 
Local values are not allowed in resource dictionary with Source set 

4015 
This Style's hierarchy of BasedOn references contains a loop. 

4016 
Can only base on a Style with target type that is base type of this style's target type. 

4017 
A Style cannot be based on itself. 

4018 
After a Style is in use (sealed), it cannot be modified. 

4019 
Must have non-null value for TargetType. 

4020 
'%0' is not a valid value for property '%1'. 

4021 
Using NavigationState requires a hidden element in HTML. 

4022 
Mouse promotion can only be suspended on a primary TouchPoint's down action. 

4023 
Navigation is prohibited for this Silverlight application. 

6000 
Unable to play protected content 

6001 
Unable to individualize due to a network or protocol error 

6002 
Unable to acquire license due to a network or protocol error 

6003 
Unable to individualize due to an installation failure 

6004 
Update of Silverlight required 

6005 
Incorrect header format for protected media file 

6006 
Unable to process license 

6007 
Unable to acquire license due to an application specific error 

6008 
Individualization disabled by user 

7000 
unexpected end of input 

7001 
unrecognized encoding 

7002 
unable to switch the encoding 

7003 
unrecognized input signature 

7004 
whitespace expected 

7005 
semicolon expected 

7006 
'>' expected 

7007 
quote expected 

7008 
equal expected 

7009 
wfc: no '' in element content 

7049 
not all chunks of value have been read 

7050 
DTD was found but is prohibited 

7051 
illegal qualified name character 

7052 
multiple colons in qualified name 

7053 
colon in name 

7054 
declared prefix 

7055 
undeclared prefix 

7056 
non default namespace with empty uri 

7057 
'xml' prefix is reserved and must have the http://www.w3.org/XML/1998/namespace URI 

7058 
'xmlns' prefix is reserved for use by XML 

7059 
xml namespace URI (http://www.w3.org/XML/1998/namespace) must be assigned only to prefix 'xml' 

7060 
xmlns namespace URI (http://www.w3.org/2000/xmlns/) is reserved and must not be used 

7061 
invalid decimal 

7062 
invalid hexidecimal 

7063 
invalid unicode 

7064 
invalid encoding 

8001 
Upgrade required 

8002 
Browser restart required