I'm not sure if anyone else has encountered this but often, when I open this particular solution, I see a whole list of errors (see below).
If I double click one of them, then Visual Studio seems to wake up and the errors relating to that particular cs file disappear. This isn't a critical issue and is more on an irritation than anything else but I wonder, is there perhaps something wrong with my code that's causing this false-positive or is it random Visual Studio behaviour?
I had this problem too.
Deleting bin and obj folders not work.
Cleaning solution not work.
Various platform I need to be as is.
Helped me close solution and delete folder .vs, which is often full of problematic mess. After opening solution all false errors disappeared.
As mentioned in a comment, you can do a Clean and Rebuild. If that does not work for you, you can browse to the solution folder and within each of the project folders delete the bin and obj folders. Then perform a build.
You may also want to look into your Configuration Manager and ensure that all of your projects are set to the same Configuration (Debug/Release) and Platform (Any CPU/x86/etc...) and marked to build for that configuration.
Finally, you may also want to check the Build Order for your solution. Ensure that projects are all built in the proper order.
-- Edit:
On thing brought up in comments that I will add here was to make sure that any library projects in the solution are added as Project References rather than referencing the output DLL directly.
Something that has only become evident in later years, and is only relevant upon reflection on this old question, is that the particular solution that we experience this issue in contains a Website project and NOT a WebApplication project. This became evident when we started to look deeper into these recurring errors and noted that they only ever related to codebehind files and all had to do with the Control Name not existing in the current context.
Amongst the various differences between the two project types, it seems that the lack of designer files for each ASP page may be a contributing factor. The error disappears as soon as you double click it potentially indicating that VS is not able to keep track of the control references until you open the relevant page / codebehind file.
We're moving over to a Web Application as a temporary measure.
Hope this insight helps someone else!
I am dealing with a really huge work such that we have a solution and there are about 100-120 projects under it. Once I was trying to launch it but it took extra long I had to cancel it. Now a number of dll files under bin folder are lost, and most of those files were created by fellow projects under the solution.
Now I cannot rebuild/build.
Till now:
-have cleaned and tried to rebuild the solutions and project folders(each folder, is directly under solution contains like 5-6 projects) one by one. I also tried rebuilding projects one by one but it took too long and was useless.
-cleaned the solution, restarted visual studio(even the computer itself), but did not worked.
-cleared the Temporary ASP.NET Files under C:\Windows\microsoft\\ TEmp... and failed to relaunch again.
-Also tried to manually add missing references to projects but since there are over 100 projects it is not useful and will not work.
Any help will be appreciated greatly.
Thank you for your time.
try everything...(in order of a little to a lot of time wasted)
Do you have bad code? Fix that first.
Clean Solution & Restart Visual Studio
Remove / Add References
Check your build order w/ larger projects and verify
Manually rebuild sub-projects
Manually copy dlls between projects into associated bin folders
Go get some coffee, play some pinball and come back tomorrow...you may think of something else in the meanwhile.
I've been there before, it is a painful process. After you do what Vignesh told you, or while you do that, you can also use Dependency Walker to help figure out which dependencies are missing. This tool from the old days is still available for free and has helped a poor soul many times over. The main download page is dependencywalker dot com.
An additional tool to use is CheckAsm. Simplified, CheckAsm is a dependency walker for .NET.
It shows all .NET assembly references for any of your .NET assemblies. This tool is located at amberfish dot net. (They have an evaluation version which is free.)
I wish you well.
We decided to delete the current solution and get it back from TFS and it resolved our problem.
We have a moderately sized solution, with about 20 projects. In one of them I have my business entities. On compiling any project, visual studio waits and hangs about one and a half minutes on this BusinessEntities project.
I tried our solution in SharpDevelop and it compiles our complete solution, in 18 seconds. Similar timing with MSBuild.
My guess is that VS is trying to find out if the project needs a compile, but this process is about 15 times slower than actually performing the compile!!
I can't switch to the great sharpdevelop, it lacks some small, but essential requirements for our debugging scenarios.
Can I prevent VS from checking this project, And have it compile the projects without such a check, just like sharpdevelop?
I already know about unchecking projects in configuration management to prevent building some projects, but my developers will forget they need to compile this project after updating to latest sources and they face problems that seem strange to them.
Edit: Interesting results of an investigation: The delay happens to one of the projects only. In configuration manager I unchecked all projects, then compiled each of them individually. All projects compile in a few seconds!! The point is this: if that special project is built directly, compiles in a few seconds, if it is being built (or skipped, because it is up-to-date) as a result of building another project that depends on it, VS hangs for about a minute and half, and then decides to compile it (or skip it). My conclusion: Visual studio is checking to know if any files are changed, but for some reasons, for this special project it is extremely inefficient!!
I'd go to Tools -> Options -> Projects and Solutions -> Build and Run and then change the "MSBuild project build [output|build log] verbosity" to Diagnostic. At that level it will include timings which should help you track down the issue.
We had the same problem with an ASP.NET MVC web project running in Visual Studio 2013. We build the project and nothing happens for about a minute or so and then the output window shows that we are compiling.
Here's what fixed it... open the .csproj file in a text editor and set MvcBuildViews to false:
<MvcBuildViews>false</MvcBuildViews>
I had to use sysinternals process monitor to figure this out but it's clearly the cause for my situation. The site compiles in less than 5 seconds now and previously took over a minute. During that minute the Asp.net compilation process was putting files and directories into the Temporary Asp.net Files folder.
Warning: If you set this, you'll no longer precompile your views so you will lose the ability to see syntax errors in your views at build time.
There is the possibility that you are suffering from VS inspecting other freshly built assemblies for the benefit of the currently compiling project.
When an assembly is built, VS will inspect the references of the target assembly, which if they are feshly built or new versions, may include actually loading them in a .Net domain, which bears all the burdens of loading an assembly as though you were going to run it. The build can get progressively slower as it rebuilds more and more projects. When one assembly becomes newer the others do a lot more work. This is one possible explanation for why building by itself, versus already built, versus building clean, all have seemingly relevantly differing results. Its really tht the others changed and not about the one being compiled.
VS will 'mark down' the last 'internal' build number of the referenced assembly and look to see if the referenced assembly actually changed as it rolls through its build process. If its not differnt, a ton of work gets skipped. And yes, there are internal assembly build numbers that you dont control. This is probalby not in any way due to the actual c# compiler or its work or anything post-compile, but pre-compile steps necessary for the most general cases.
There are several reference oriented settings you can play with, and depending on your dev, test, or deployments needs, the functional differences may be irrelevant, however may profoundly impact how VS behaves and how long it takes during build.
Go to the references of one of the projects in Solution Explorer:
1) click on a reference
2) open the properties pane if its not (not the Property Pages or the Property Manager)
3) look at 'Copy Local', 'Embed Interop Types', 'Reference Output Assembly'; those may be very applicable and probably something good to know about regardless. I strongly suggest looking up what they do on MSDN. 'Reference Output Assembly' may or may not show in the list.
4) unload the project, and edit the .proj file in VS as text. look for the assembly reference in the XML and look for 'Private'. This means whether the assembly referenced is to be treated as though its going to be a private assembly from the referencing assemblies perspective, vs a shared one. Which is sort of a wordy way of saying, will that assembly be deployed as a unit with the other assemblies together. This is very important toward unburdening things. Background: http://msdn.microsoft.com/en-us/magazine/cc164080.aspx
So the basic idea here is that you want to configure all of these to be the least expensive, both during build and after deployment. If you are building them together, then for example you probably really don't need 'Copy Local'. Id hate to say more about how you should configure them without knowing more about your needs, but its a very fine thing to go read a few good paragraphs about each. This gets very tricky however, because you also influence whether VS will use the the stale old one when resolving before the referenced one is rebuilt. As a further example explaiing that its good to go read about these, Copy Local can use the local copy, even though its stale, so having this set can be double bad. Just remember the goal at the moment is to lower the burden of VS loading newly built assemblies jsut to compile the others.
Lastly, for now, I can easily say that hanging for only 1.5 mins is getting off very lucky. There are people with much much worse build times due to things like this ;)
Some troubleshooting idea's that have not been mentioned:
Clean solution?
Delete Obj and Bin folders plus the .suo file? FYI, neither Clean nor Rebuild will delete non-build files, eg files copied during a pre-build command.
Turn off VS scanning outside files. Options > tools > environment > document > detect when file is changed outside the environment?
Rollback SVN history to confirm when it started to occur? What changed? If the project file on day 1 takes the same time, recreate the project, add all the files and build.
Otherwise could you please run Process Monitor and let us know what Visual Studio is doing in the prep-build stage?
Sounds silly, but remove all breakpoints first. It sped up my pre-build checks massively - still don't know why though.
Based on the (limited) information provided one possibility is that there could be a pre-build action specified in the project file that is slow to compile.
Try disabling platform verification task as described here.
If your individual projects are compiling correctly then all you can do is change order of compilation by setting dependent projects explicitly in configuration.
Try to visualize your project dependency hierarchy and set dependent projects. For example, if your business entities project is referenced in each project, then in configuration of each project, this project must be selected as dependent.
When an explicit build order is not set, visual studio is analyzing projects to create an order of building project. Setting explicit dependent projects wiki make visual studio skip this step and use the order provided by you.
With such an extreme delay on a single project and no other avenue seeming to provide a reason I would attempt to build that specific project while running procmon from sysinternals and filter out all the success messages. You could probably also narrow it down to just the file system actions as well. From your description I might guess that the files are being locked by an external source like the event collection or workflow management process services.
Other things to consider would be whether or not this is a totally clean build machine or if it has been used to perhaps test the builds as well? If so, is there a chance that someone mapped an IIS application path to the project directly or registered it as a service location?
If you run procmon and see no obvious locks or conflicts I would create a totally new solution and project and copy the files over to see if that project also has the same delay. If it does have the same delay I would create a sample project of the same type but generic data (essentially empty) and see if that too is slow. If the new project with the same files builds fine you can then diff the directories to see what the variance is that causes the problem (perhaps a config or project setting).
For me, thoroughly disabling code analyzers helped per instructions here:
https://learn.microsoft.com/en-us/visualstudio/code-quality/disable-code-analysis?view=vs-2019#net-framework-projects.
I thought my code analyzers were already off, but adding the extra xml helped.
Thanks Kaleb's for the suggestion to set "MSBuild project build [output|build log] verbosity" to Diagnostic. The first message took more than 10 seconds to display:
Property reassignment: $(Features)=";flow-analysis;flow-analysis" (previous value: ";flow-analysis") at C:\myProjectDirectory\packages\Microsoft.NetFramework.Analyzers.2.9.3\build\Microsoft.NetFramework.Analyzers.props (32,5)
Which led me to the code analyzers.
Just in case someone else trips into this issue:
In my case the delay was being caused by an invalid path entry in "additional include directories" that referred to a non accessible UNC location.
Once this was corrected, the delay disappeared.
I am working on a C# application which I have divided it to few projects. Recently when the solution becomes larger, I get different errors such as MissingMethodException or even worse, DLL not found messages.
The only solution is to delete my bin folder and build the project again.
I wonder if this is a common problem with visual studio or might be I am doing something wrong?
UPDATE:
I am working on a winforms soloution, while one project is the form and other projects are user control, data models and etc.
I do reference the needed project in other projects using the visual studio's add reference option.
UPDATE 2
I am suspecting when I have a new .cs file to extend a class using partial keyword in any projects this happens!!!! I am 99% sure, I am going to check some more times to see of this is really the case!
It's not really a common problem but messy things can happen some times on visual studio.
What I would do is to check the settings and dependencies of every project and check things like they build in the correct order, platform, output path, etc. In our case, some times when the solution travels to many developers/computer settings can alter.
Also another thing you could do would be to copy the main project to a new solution and add the rest of the projects. This has worked form me in a similar situation.
I hope I gave you some ideas.
I have a large windows application.
Recently when I make any change in the source code and run the project normally with or without debug, the changes are not made.
I tried to rebuild it, and everything goes fine,
now every change I made to the source code I have to rebuild the project then run it so that the changes are taking effect.
also I can't debug until I rebuild the solution.
my project is attached to source safe control.
any help is appreciated.
You frequently see this happen when a project gets deselected from the "Current Build Configuration" Dialog in visual studio. Try checking there to see if your project is unchecked. I think you can get to that menu by clicking the dropdown that says Debug/Release, and clicking manage/edit.
This is an old question but I happened to face a similar challenge. Well, for the benefit of someone who may experience the same here is how my problem was solved. I had a multi-project solution where some project depended on the source code from the other projects. Just before giving up and continue with the rebuild thing, I decided to check on the Build Dependencies=>Project Dependencies(Right-Click on the project). I found that the problematic code was from a Class Library that was not part of the dependencies(Unchecked). When I Included the project in the dependencies my problem vanished into thin air.
If you are referencing a .dll whose code is in another project you will need to build the project before the changes are reflected even if both projects are in same solution. sadly there is no running away from it.
Go to your configuration Manager and make sure build checkbox is selected for your project.
other thing you can try is:
Go to tools > Options>> A window will pop up> Under Project and Solutions > select Build and Run
Make sure Before building is set to Save all changes
(Copied from answer by amit dayama at https://stackoverflow.com/a/32820701/3195477)
I have faced the same problem because I have done some unsafe modifications upon the project names and have used find/replace upon the solution. Which resulted in a hidden exception in the android manifest file and exactly at the package name.
I avoid all types of headaches, I have created a new blank project with the desired name and namespaces and then moved the functional files, resource files and then modified static files like manifest and so on.
Never use unsafe method for project data configuration & modification