C#: An exception has been encountered. This may be caused by an extension

Question

I'm running with VS-2013 Ultimate. While executing my code, I'm getting this error message box:

An exception has been encountered. This may be caused by an extension

When entering the log file (the path is mentioned on the message), I'm get this exception:

  <entry>
    <record>905</record>
    <time>2014/08/22 15:46:25.494</time>
    <type>Error</type>
    <source>Editor or Editor Extension</source>
    <description>
        System.NullReferenceException: Object reference not set to an instance of an object.&#x000D;&#x000A;
            at Microsoft.VisualStudio.Debugger.Parallel.UI.ThreadMarkerGenerator.LocationMatchesTagger(DocumentContext location, MarkerTagger tagger)&#x000D;&#x000A;
            at Microsoft.VisualStudio.Debugger.Parallel.UI.ThreadMarkerGenerator.&lt;&gt;c__DisplayClass1.&lt;GetMarkersForTagger&gt;b__0(ThreadMarker marker)&#x000D;&#x000A;
            at System.Linq.Enumerable.WhereListIterator`1.MoveNext()&#x000D;&#x000A;
            at Microsoft.VisualStudio.Debugger.Parallel.Extension.MarkerTagger.&lt;GenerateTagList&gt;d__a.MoveNext()&#x000D;&#x000A;
            at System.Linq.Buffer`1..ctor(IEnumerable`1 source)&#x000D;&#x000A;
            at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)&#x000D;&#x000A;
            at Microsoft.VisualStudio.Debugger.Parallel.Extension.MarkerTagger..ctor(ITextBuffer buffer, ITextDocument document)&#x000D;&#x000A;
            at Microsoft.VisualStudio.Debugger.Parallel.Extension.MarkerTaggerProvider.CreateTagger[T](ITextBuffer buffer)&#x000D;&#x000A;
            at Microsoft.VisualStudio.Text.Tagging.Implementation.TagAggregator`1.GatherTaggers(ITextBuffer textBuffer)
        </description>
  </entry>

I'm sure that this code already worked well in the past. What could be the reason?

http://stackoverflow.com/questions/4660142/what-is-a-nullreferenceexception-and-how-do-i-fix-it — Neil Smith, Aug 22 '14 at 15:56
It's an exception in Visual Studio and has nothing to do with your code, unless you are debugging an Extension... — dee-see, Aug 22 '14 at 15:56
It's telling you there's a problem with an extension.. Are you sure it's your code? — tbddeveloper, Aug 22 '14 at 15:57
Your error is not related to visual studio 2013. Debug your code after learning what a nullpointer exception is from the other responses. — RandomUs1r, Aug 22 '14 at 15:57

score 11 · Answer 1 · answered Sep 17 '15 at 23:43

11

Fixed that problem by deleting the following folder:

C:\Users{username}\AppData\Local\Microsoft\VisualStudio{version-number}\ComponentModelCache

answered Sep 17 '15 at 23:43

kareemborai

394
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score 2 · Accepted Answer · answered Aug 22 '14 at 16:44

2

Use the latest update of VS.

Visual Studio exception thrown in Microsoft.VisualStudio.Debugger.Parallel.dll in very rare circumstance

We are happy to let you know that this issue has been fixed in Visual Studio 2013 Update 2.

answered Aug 22 '14 at 16:44

Kevin Panko

8,356
19
50
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1

I'm upgraded to VS2013 update3 and now it's working good! thank you! – No1Lives4Ever Aug 23 '14 at 17:02

score 0 · Answer 3 · answered Apr 08 '17 at 16:24

I had this same problem with Visual Studio 2017. I tried the above steps but still got the popup along with the windows sound. Also, some of my (limited) extensions would not work (e.g. add new file, shift F2).

I found out that the temp folder was so full that Visual Studio has problems in creating temp files.

Solution: Delete everything here ->

C:\Users\YOURUSERNAME\AppData\Local

I had 5 GB of stuff here and Visual Studio started to run smoothly after a restart.

C#: An exception has been encountered. This may be caused by an extension

3 Answers3