Visual Studio does not recognize a referenced assembly? - c#

Opened an old project from years ago. Build fails because Visual Studio (2019) does not recognize an assembly that is clearly there - specifically, Autofac.
You can see it in project references (not marked as missing)
You can see it in the Object Browser, listing all the types referenced in the code
But in code, none of the types show up, gone AWOL.
What is going on here? Intellisense doesn't even pick up types
(Tried cleaning, rebuilding, re-importing packages)

Okay, this is what worked. I had to remove the reference to the Autofac dll, and then add it back. Note - I added it back from the same exact location, the same exact version. But after this, Visual Studio 'magically' recognized it.
If you come across a similar problem, and nothing else works, give it a try. I don't know the reason, I can only assume this is some sort of a bug in Visual Studio.

Related

Visual Studio 2019 intellisense shows red squiggles under every single namespace that is not a .NET one

Visual studio 2019 intellisense shows red squiggles under every single namespace that is not a .NET one. The project builds and runs fine. If I open the solution in VS 2017 it opens fine with no errors.
I have deleted the .vs folder. How can I solve this problem?
edit:
It seems the shared projects have been lost. If I right click to add a reference the other projects cannot be found. I tried removing a project from the solution and re-adding it but the "shared projects" list is still empty. I suspect this is related to problem where intellisense can't find them either.
If I open the solution up in VS2017 after this, everything works fine so it appears to be related to VS2019 only.
Our solution is documented here:
https://github.com/dotnet/roslyn/issues/40082
I was able to track down the root cause for this issue, and also
provided a workaround to #rolandh offline.
Tagging #jasonmalinowski, who is expert on VS project system layer on
our team, and #tmat who has been investigating how to properly report
VS-specific diagnostics in Roslyn. Let me expand on the findings:
Provided solution has a two projects which have a circular reference
Project P1 has a ProjectReference to project P2 and project P2 has a metadata Reference to P2.dll. Latter gets converted to a project
reference via our metadata to project reference conversion logic.
Above configuration leads our VS project code to throw an
InvalidOperationException in CheckNotContainsTransitiveReference
over here when attempting to add project and metadata references.
Above exception seems to get handled somewhere down the call stack,
so there is no user visible impact. However, it causes the project
state for P1 to get corrupt - it ends up with no documents, no
references, etc. This leads to a ton of cascading intellisense
errors in all projects referencing P1.
Building the project/solution on command line succeeds as P1's
reference to P2.dll is unnecessary.
Unfortunately, the above InvalidOperationException does not
translate to any diagnostic in the error list, so user is given no
information about what went wrong under the covers and how to
resolve their issue. Ideally, the circular reference, or in fact any
such project system anomalies for which we throw exceptions in the
Workspace layer, should be translated to diagnostics in error list
by VS layer, so it helps the user towards fixing their
project/solution. #jasonmalinowski do we have any issue tracking
such work? I can file one otherwise.
Basically somehow we got a circular reference in our projects (not possible via the UI) which causes a bug in the intellisense engine.
Removing this circular reference resolved the issue.

Intellisense showing identifier not found error when everything build successfully

I am working on a small project involving a wpf-based UI program when I come to a intellisense problem. It constantly complains that several identifiers (class/method/property) cannot be found, and most of those are from another assembly. Similar issue has been asked by many other users of visual studio:
WPF assembly reference missing - project still building
Type or namespace cannot be found, when reference does exist
Getting "type or namespace name could not be found" but everything seems ok?
If the promble only happens on types in referenced assemblies I might just overlook it. But now even some types in the same assembly are determined 'missing' by intellisense. Today I created a new custom Window in this wpf project, and visual studio auto generated code for further use as follows:
public partial class ReceiveTest : Window
{
public ReceiveTest()
{
InitializeComponent();
}
}
Then intellisense told me that identifier 'InitializeComponent' cannot be found, and every control this window owns cannot be found either. This is really upsetting since it makes intellisense completely useless. Normally these 'missing' identifiers are declared in FileName.g.i.cs and managed by visual studio itself, however it seem visual studio somehow failed to recognize it.
Now I have done everything I can including solutions given in above links but failed again and again. Could anyone explain this problem and show me a way to solve it? I would be very very grateful.
P.S. I am using visual studio 2017 and PowerTool addon
Upgrading Test project from 2010 to 2017
Following this up on a recent problem with a test project on VS2017 after upgrade from 2010. Tried everything to get rid of the squiggly red and they wouldn't go.
Problem was that 'namespace.zone.section' had 'namespace' not found when it was there and seen by intellisense etc (and in some cases 'zone' or 'section')
Deleted sou files
Deleted project files
Deleted the references
Reapplied all after clean, restart, restart
server and all the above.
Still problem persisted.
So I deleted the test project (imported form 2010) recreated the project in 2017, copied all the original test classes into new project, added back all the other projects (supporting the tests), added moq etc back in. Only took about 20 mins.
And ... compiled and worked.
Conclusion was that the original project file (test project) had something in it that didn't get upgraded and screwed it all up. Anyway it is all fine now.
I post this so you don't have to wast your time.

In Visual Studio 2015, auto-generated "object" text is replaced with "System.Object" and doesn't compile

So I'm writing a portable class library in Visual Studio 2015. A couple of days ago as I was writing code any auto-generated uses of the object keyword started being replaced with System.Object. Furthermore, they don't compile (the type name Object does not exist in System) so I have to go through and manually replace each instance with object. As far as I know I didn't change any settings that could have caused this (the only time I've even been into the 'Options' or 'Customize' menus in the past week was to change a keybinding).
This only seems to affect my project in particular and if I make a new project it isn't an issue. I've tried using the repair function in Visual Studio but that didn't fix it. Migrating all the project's files over to another project isn't really a viable option because of the size of the project.
Any ideas?
Edit: I'm not sure if this just started, but I've just noticed that the string keyword isn't being generated and System.String is being generated in its place. This also doesn't compile for the same reason.

Problems using Excel Interop in SSIS

I am using Excel Interop in a SSIS Script task on a server with Excel 2007 installed.
Since a few days, errors appear when I try to open the script task. Whenever I open the code, the references to Interop are marked with a yellow warning sign and the namespace cannot be referenced.
I cannot add it again via "Add References", and when I try to add Excel Object Library in the COM Tab, it is also added with yellow warning signs (I couldn't find an error message for that).
However, when I don't save the changes and just run the whole project, it works without problems. Interop therefore seems to work, but it is somehow not found in Visual Studio.
I tried to install the PrimaryInteropAssemblies again, without success. The interop assembly is still found under c:\windows\assembly. The strange thing there is, that there is no processor architecture given for the assembly, while it is on my development machine.
I tried to uninstall the assembly to then install it again, but couldn't do it due to insufficient rights (even as administrator).
I had to install the Windows SDK a few days ago to use gacutil, could that be the reason for the missing reference?
The programming language is C# 2010 with Visual Studio 2010.
Thanks,
EDIT: I found a solution, although it still doesn't work as it is supposed to be. Here is how it works:
The problem can be solved by setting the "specified version" property of the reference to false. New projects can use the interop by referencing to it under C:\Windows\assembly\GAC\Microsoft.Office.Interop.Excel\12.0.0.0__71e9bce111e9429c\Microsoft.Office.Interop.Excel.dll
with a bit more of experimenting, I finally found a solution to the problem and want to share it here. It definitely isn't as it is supposed to be, and I would still really appreciate if somebody knew the reason behind that problem.
The problem can be solved by setting the "specified version" property of the reference to false. New projects can use the interop by referencing to it under C:\Windows\assembly\GAC\Microsoft.Office.Interop.Excel\12.0.0.0__71e9bce111e9429c\Microsoft.Office.Interop.Excel.dll

Why can't I reference my class library?

I have a solution that contains a website and a class library in Visual Studio 2008.
I then have another web site project outside of the solution that needs to reference the class library. I right click the Bin folder or Project and select Add Reference, then select my Class Library Project, it adds the 15 or so DLLs that the class library needs to the websites bin folder, but none of the .cs files recognize the using statements.
using MyLibrary.MyFolder;
It says that it can't resolve it, and ReSharper just says it can be safely removed since it's not being used.
ReSharper can recognize that it needs the reference and suggests that it "Reference MyLibrary and use MyFolder". I'm not sure why it's suggesting I add a reference I already have. When I go with the suggestion, I get the error
"Failed to reference module. Probably, reference will produce circular dependencies between projects."
I've tried going to the websites property pages and removing all the references and re-adding them, but it gives the same errors. Any ideas why this isn't working?
Also, check that the new solution's projects run against a compatible framework to the project you're trying to include. I was trying to include a reference to a 4.0 project in a 3.5 project.
I found how to fix this issue (for me at least). Why it worked, I'm not sure, but it did. (I just tried against a second website that was having the same problem and the following solution worked for that as well).
I tried the normal cleaning of the projects and rebuilding, shutting down all my Visual Studio instances and restarting them, even tried restarting my computer.
What actually worked was opening up the project in Visual Studio, closing all the open tabs, and then shutting it down.
Before I had left the tabs open because I didn't think it mattered (and I hardly ever close the tabs I'm using).
One possibility is that the target .NET Framework version of the class library is higher than that of the project.
I had a similar problem, will all my references being buggered up by Resharper - The solution which worked for me is to clear the Resharper Cache and then restarting VS
tools->options->resharper->options-> general-> click the clear caches button and restart VS
I had a similar problems where VS would sometimes build and sometimes not. After some searching and attempts I discovered that I had an ambiguous reference to a class with the same name in different libraries ('FileManager'). The project that would not build were my Unit Tests that reference all modules in my solution. Enforcing the reference to a specific module sorted things out for me.
My point is: Rather than blaming ReSharper or VS, it may be a good idea to double check if there really isn't some kind of circular reference somehow. More than often, classes with the same names in different modules could cause confusion and is often a symptom of bad design (like in my case).
This sounds like a similar issue with ReSharper:
http://www.jetbrains.net/devnet/thread/275827
According to one user in the thread forcing a build fixes the issue (CTRL+Shift+B) after the first build..
Sounds like an issue with ReSharper specifically in their case.. Have you tried building regardless of the warnings and possible false errors?
Since they are both in the same solution, instead of adding a reference to the DLL, add a reference to the class library project itself (the Add Reference dialog will have a tab for this).
Ahh, it's a different solution. Missed that. How about you try instead of adding a reference to the project addding a reference to the compiled DLL of your class library. The Add Reference dialog has a Browse tab which does this.
After confirming the same version of asp.net was being used. I removed the project. cleaned the solution and re-added the project. this is what worked for me.
If you're referencing assemblies for projects that are in the same solution, add a Project reference (using the "Projects" tab) rather than browsing for the dll in the \bin\Debug (or \bin\Release) folder (using the "Browse" tab). See screen shot below. Only browse for the assembly/dll file if it's considered an external assembly.
I deleted *.csproj.user ( resharper file) of my project, then, close all tabs and reopen it. After that I was able to compile my project and there was no resharper warnings.
I had this problem. It took me ages to figure out. I had people over my shoulder to help. We rebuilt, cleaned and restarted Visual studio and this didn't fix it. We removed and re-added the references...
All to no avail.... Until!
The solution to my problem was that my class declaration was spelt incorrectly.
Before you start judging me harshly, allow me to explain why it wasn't stupid, and also why this mistake could be made by even the most intelligent of programmers.
Since the mistake was early on in the name, it wasn't appearing in the intellisense class listing when I began typing.
e.g.
Class name:
Message.cs
Declaration:
public class Massage
{
//code here
}
At a glance and in a small font, Massage looks identical to Message.
Typing M listed too many classes, so I typed e, which didn't appear in the mistyped version, which gave the impression that the class wasn't being picked up by the compiler.
I had a similar issue in VS 2010, when creating a test project for an MVC 2 application.
The symptoms were identical.
The message from ReSharper was somewhat misleading. For a moment I completely ignored ReSharper and did it the "manual VS way":
I cleaned the solution.
I manually added the reference to the MVC project.
I manually added the using directives.
ctrl-shift-b
At this stage I got a compilation error: I should have referenced the System.Web.Mvc assembly in my test project (sigh). Adding this reference causes the project to compile. The ReSharper issues remain, but the ReSharper test runner works.
When I restart VS, the ReSharper errors are gone too. I'm not sure if the restart is required - simply closing the .cs file might be enough.
From now on, when I see the ReSharper message
Failed to reference module. Probably,
reference will produce circular
dependencies between projects.
I'll read
Failed to reference module. Probably,
reference will produce circular
dependencies between projects,
or you are missing some references to dependencies of the reference's dependencies.
Another possible fix that just worked for me:
If you have Assembly A, which references Assembly B, both of which reference a non-project (external) assembly X, and Assembly B's code will not recognize that you have referenced X, then try the following steps in order:
Drop reference to X from BOTH A and B
Recreate reference to X in B
Recreate reference to X in A
Apparently, VS will not recognize a reference to an external assembly in a project that is a dependency of another project that already references the external. By setting up the references again from the ground up, you overcome this. It's just very odd.
I faced this problem, and I solved it by closing visual studio, reopening visual studio, cleaning and rebuilding the solution. This worked for me.
If using TFS, performing a Get latest (recursive) doesn't always work. Instead, I force a get latest by clicking Source control => Get specific version then clicking both boxes. This tends to work.
If it still doesn't work then deleting the suo file (usually found in the same place as the solution) forces visual studio to get all the files from the source (and subsequently rebuild the suo file).
If that doesn't work then try closing all your open files and closing Visual studio. When you next open Visual studio it should be fixed. There is a resharper bug that is resolved this way.
I had stumbled upon a similar issue recently. I am working in Visual Studio 2015 with Resharper Ultimate 2016.1.2. I was trying to add a new class to my code base while trying to reference a class from another assembly but Resharper would throw an error for that package.
With some help of a co-worker, I figured out that the referenced class existed in the global namespace and wasn't accessible from the new class since it was hidden by another entity of same name that existed in current namespace.
Adding a 'global::' keyword before the required namespace helped me to reference the class I was actually looking for. More details on this can be found on the page listed below:
https://msdn.microsoft.com/en-us/library/c3ay4x3d.aspx
If both projects are contained within the same solution, it will be more apropiate if you add the reference for the project you need, not its compiled dll.
I had the exact same problem.
I tried closing Visual Studio numerous times, I tried deleting and adding a new class library.Checked if I had the right version, if I had referenced it in the target project. Nothing worked.
Then I thought maybe, just maybe I cannot reference the library because it was empty... and that was it.
As soon as I added a class to it the problem was fixed. So if you have tried everything and you are close to losing your sanity. Just try adding something to the class library.
the solution for was just adding the access modifier
my class didnt have any access modifier then i just added public and it worked!
Contracts class library:
namespace Contracts
{
public interface ILoggerManager
{
void LogInfo(string message);
void LogWarn(string message);
void LogDebug(string message);
void LogError(string message);
}
}
Logger service class library:
using Contracts;
using NLog;
public class LoggerManager : ILoggerManager
{
private static NLog.ILogger logger = LogManager.GetCurrentClassLogger();
public LoggerManager()
{
}
}
I tried various solutions for this issue. An old WebForms application refused to acknowledge the existence of a library even though a reference existed.
Oddly, what worked was to add and reference the class library in Visual Studio 2022, safe the project, then reopen in an earlier version of Visual Studio.
My solution was simple, but I'll share it in case someone else has the same issue and finds this question by googling like I did.
It turns out that the most recent build of the supporting DLL was done in Debug mode, and my code was looking at the Release version of the DLL. I rebuilt the DLL in Release mode and all is working properly.
Unfortunately the only thing that worked for me was completely deleting and recreating the class library project, after having temporarily copied the class files in it elsewhere. Only then would the ASP.Net web project recognise the using statements that referred to the class library project. This was with Visual Studio 2010, not using ReSharper.
I had similar issue. What worked for me is that I had added wrong Class Library from visual studio. I added by using the search feature of visual studio.
What I needed to do was Add New Project > Visual C# > Class Library. And this newly added class library is the right one and can now be added as reference to any project.
You may forget to add reference the class library which you needed to import.
Right click the class library which you want to import in (which contains multiple imported class libraries), -->Add->Reference(Select Projects->Solution->select the class library which you want to import from->OK)

Categories