After installing the ASP.NET and Web Tools 2015 (RC1 update 1) I get the following error within ASP.NET MVC 4 projects when opening *.cshtml files:
Object reference not set to instance of an object
I get the same error message even if I start a new ASP.NET MVC 4 project and try to open a *.cshtml file there.
I'm using Visual Studio 2015
Maybe this helps:
and run devenv /resetuserdata.
Expect, that all of your user settings such as Visual Studio layout, linked Microsoft account or start page might disappear.
Delete %LocalAppData%\Microsoft\VisualStudio\14.0\ComponentModelCache and restart Visual Studio.
Alternatively, use the Clear MEF Component Cache extension.
For me,
VsHub.exe.After that, everything works like a charm again!
I solved it doing
run devenv /resetuserdata
in this path:
[x64] C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE
I assume that in x86 it works in this path:
[x86] C:\Program Files\Microsoft Visual Studio 14.0\Common7\IDE
It's recommended to try any or all of the following:
Restart Visual Studio
Try Running As Administrator (right-click Visual Studio and choose "Run As Administrator")
Check for any updates for Visual Studio (download and install them if any are available)
Try opening a different solution / project
If problems persist, you might try the following options:
Restart your local machine
Attempt to reset Visual Studio to System Defaults (this can be done from the options within Visual Studio)
Attempt to repair your Visual Studio installation
In the hopes it might narrow things down/help someone, I did an investigatory approach. For me, I initially moved the folder at C:\Users\{user}\AppData\Local\Microsoft\VisualStudio to My Documents and allowed Visual Studio to re-create it by re-launching it. This removed the errors. So I moved everything back, one-by-one, and restarted Visual Studio each time until I discovered the culprits. These folders were fine to move back in:
These files were fine to move back in/overwrite the auto-generated ones:
These files were fine to move back in. Each was in my old copy, and not initially re-created when I re-launched VS:
These caused problems - delete these files and re-launch VS to allow it to re-create them:
These are the errors from those last .NETFramework files (which I do not get if I do not add them back in):
01:10:11.7550: Referenced file 'C:\Program Files (x86)\Microsoft Visual Studio 14.0\JavaScript\References\libhelp.js' not found.
01:10:11.7550: Referenced file 'C:\Program Files (x86)\Microsoft Visual Studio 14.0\JavaScript\References\sitetypesWeb.js' not found.
01:10:11.7550: Referenced file 'C:\Program Files (x86)\Microsoft Visual Studio 14.0\JavaScript\References\domWeb.js' not found.
01:10:11.7550: Referenced file 'C:\Program Files (x86)\Microsoft Visual Studio 14.0\JavaScript\References\underscorefilter.js' not found.
01:10:11.7550: Referenced file 'C:\Program Files (x86)\Microsoft Visual Studio 14.0\JavaScript\References\showPlainComments.js' not found.
I might just need to re-install/repair the JavaScript Language Service plug-in, so it might be un-related. But definitely devenv.exe.config and ComponentModelCache need to go to correct the "object reference not set to an instance of an object" error.
For me, ASP.NET 5 is not yet required, I removed update, and then reinstalled ASP.NET 4.5. It's a bit tricky:
No longer follow the notification of update in Visual Studio 2015!!!
After trying the top answer, I found that you must also restart the computer. The error may be part of a git issue as well where restarting your computer will reset.
I was getting an exception every time I tried to create a "new" project.
My solution was:
Go menu Tools → Extensions and Updates
Check the "Updates" link... There was an update to Microsoft ASP.NET and Web Tools. Install it.
That fixed it for me.
In my case (not necessarily be the solution for you, but it may be helpful for someone), the solution was:
Go menu Tools → Extensions and Updates
Select the Online tab from the right panel
Search for the words web tools, and then select Microsoft ASP.NET and Web Tools and install it.
In my case, this was missing from my computer because of a lot of repairing operations for Visual Studio.
I was getting this exception every time I created a "new" project.
My solution was:
That fixed it for me.
Unfortunately, I ran into another exception:
"Exception has been thrown by the target of an invocation"
I disabled the FIPS setting Enabled DWORD value to zero.
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\FipsAlgorithmPolicy]
Enabled=dword:00000000 And All fixed.
I have been fighting with this during the whole weekend. But it's pretty easy to do it. What I did was to click on repair rather than uninstall. After repairing, I clicked on restart directly. After that, everything is working perfectly. You should try this, may be it can work also for you!!!
Restarting Visual Studio did it for me. On the next run, it displayed a "Scanning new and updated MEF components ..." and then it executed normally.
It seems to be related to Windows update somehow, although I don't have proof.
Delete bin and obj folders in all projects of that solution.
Seems like those folders were having old files generated by some older version of visual studio, which are not compatible with new version of visual studio.
Goto windows+R and type %temp% and hit enter. delete the temp folder and files and then try opening the same
The solution to the issue when i had this earlier today was that there was an additional set of tags bolted on the end of my Web.config. Once removed the functionality returned.
I was getting similar error in VS2017 while trying to publish my solution to Azure.
This algorithm helped me to resolve it:
Note that this will remove your Visual Studio's recent files / projects from it's history and also linking to MS account.
This method is slightly different from the Top answer. Here you don't have to delete other folders except renaming abovementioned one.
Problem: My VS 2015 was throwing up error after I installed SSDT. Whenever I clicked on Tools >> Extensions and Update it was throwing "Object reference not set to an instance of an object" error. When I tried to open a solution it threw some provider not set correctly.
Solution: After many hours of research trying out all the solutions previously mentioned by others didn't solve my problem. Every time the error popup was pointing to check the ActivityLog.xml. But I was ignoring it. After hours of frustration I decided to read the error carefully and looked into ActivitLog.xml and found that it was looking for "Could not load file or assembly 'System.Collections.Immutable, Version=1.1.37.0". So I just started searching for this assembly and stumbled upon this link https://sergeytihon.com/2015/12/01/how-to-restore-viual-studio-2015-after-update-1-dependency-dance/ and followed the steps there, which fixed my issue.
Went into %LOCALAPPDATA%/Local\Microsoft\VisualStudio\14.0\devenv.exe.config and searched for "System.Collections.Immutable" and change newVersion from 1.1.36.0 to 1.1.37.0
Final config should look like this
<dependentAssembly>
<assemblyIdentity name="System.Collections.Immutable" publicKeyToken="b03f5f7f11d50a3a" culture="neutral"/>
<bindingRedirect oldVersion="1.0.27.0-1.1.65535.65535" newVersion="1.1.37.0"/>
</dependentAssembly>
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