I am using Visual Studio 2005, .NET 2.0
I am not really sure yet under what circumstances it happens, but here is the scenario:
I have a solution with a project structure like this: A library project Foo, a library project Bar which references Foo, and a library project Quux which references Foo and Bar.
Compiling fails with the Error message "Metadata file 'Foo.dll' could not be found" from Bar, and "Metadata file 'Foo.dll' could not be found" and "Metadata file 'Bar.dll' could not be found" from Quux.
Looking in my target directory (I have a combined target directory for all 3 projects), it is empty, so no project at all is compiled. Now I can get that Bar and Quux fail if there is no output from Foo. Problem is: Why does Foo silently fail? There is no error from it, and just building Foo instead of the entire solution works fine.
The "funny" thing is, after just pushing the build button again, the Foo.dll file appears, Bar no longer complains but does not produce any output file either, and Quux complains about missing Bar.dll. Pushing the button again, the Bar.dll appears, there are no more errors but no Quux.dll. Only after pushing the button yet again, the Quux.dll appears, once again with no errors.
The project dependencies are all set correctly, the solution build order says exactly the right thing.
I have even tried creating a new solution and new project files, then adding the sources again to those. No joy, either. Same thing happens.
I am completely stumped. Does anyone know a way out of this mess?
You should have separate output directory for each project. Each time a project builds, it clears the output directory, so it won't find any dependencies on the next one.
Don't fear losing any DLLs, they'll be copied on each bin directory where they are needed.
I think a work around to your problem could be using post build events that deletes previous version of your dlls and copies the new ones to your combined target directory.
When you set up the three projects to work this way, you will find that you are compiling each project to it's correspondent bin folder and to a combined target directory. There is a second thing you should do if you decide to work with this, set up for each project in your solution a reference path pointing to the combined target directory. Compiling order must still exist.
This way each project dll will be found in the combined target directory, each time you compile.
Although, this solution has it's own problems such as when a post-build event forgets to wrok properly; but it's rare.
Hope this helps
The problem is build order. If some project depends on another then that second project must be built first. Use build dependencies in the solution properties to overcome this.
Check you build order so that all seems right there..
Try to run a clean solution and build again is this when it happens?
Drag your project file into note pad and Find with "Import" tag
and replace that tag with this
Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets"
Its should work
For reasons unknown, this happened to me with Visual Studio 2013 in the middle of a morning's work. One build, it was updating the dll, the next, it just wasn't, even though the build seemed to go smoothly. I finally addressed it by deleting the existing dll. With no pre-existing dll, the build had to provide a new one.
I agree that each project should have its own target directory. I have tried to get cute with this and it always causes more trouble than whatever I was trying to get around.
I have a vs19 , 5 project solution. I just added a new console app. THis app started suddenly compiling without complaint but did not produce files. the unit test project that depends on it complained.
I did the usual
clean / rebuild
clean / rebuild each project in order
check the project dependencies and the build order
restart vis studio (in know its 2020 and i still have to restart vs sometimes)
faced w/ the prospect of just creating a new project, i decided to try one other thing
removed all references to other projects
commented out all the code that depended on these.
i was left with pretty much a main() that returned a 0
this compiled and produced files
one by one i added the references back until everything was there.
uncommented the code.
at the end of this exercise things worked.
I can not tell you what changed.
Thought I would offer this as a trouble shooting method.
Related
I am working on a rather large project in visual studio, and I have several references to other solutions and projects within my current solution. One of my user controls resides in a separate solution, so I need to consistently be able to update the DLL to fit any changes to my code. The only problem is, Visual Studio will not update my references unless I go through a long, meticulous process which I will try to describe now:
First, I must clean and rebuild the solution that contains the changed code. Here is a snippet of the class I need to update:
I just added the highlighted property, so my other project does not recognize it yet. I used blank properties like HelloWorld and ISuddenlyDespiseYogurt because they are easy to spot in code and properties will show in the compiled version of the code.
Secondly, I must go to the project I am trying to use the DLL in, delete the reference, and re add it.
I right click on the reference I want, click delete, then right click on the "References" tab, press "Add Reference", then I use the file path of my other solution and update the reference.
Lastly, I must restart Visual Studio and reopen the project I was working on.
And now our new property is recognized by my project. This solution works every time, but it is a ridiculously annoying workaround, and I am hoping someone out there knows how to make this process much easier.
This is the closest thing I can find to a similar problem on StackOverflow, and the rest of the internet is no help. If anyone has any clue how to fix this problem, I would very much appreciate your insight.
I have a feeling that your project is copying the library .DLL to your project folder, instead of linking over to the Hamilton.HST project's Release folder.
Two things I would check from your side: when you're linking the reference and clicking 'Browse', where exactly are you grabbing the .DLL from? Hopefully the Release folder, or some other output that changes when the Hamilton.HST project is recompiled. And second, check your main project and the properties on the Reference, to make sure it's pointed to that Hamilton.HST folder (like I said, I have a suspicion its pointing to somewhere in your second project's folder, and that VS copied the DLL over instead of linking.)
I managed to fix the problem, hopefully for good. For the sake of anyone else who may have this problem, here is my solution:
I went into the "Properties" tab of my project, by right clicking on the project name in Solution Explorer and clicking "Properties". I then navigated to "Build Events", where I saw something like this:
The first two lines were there when I opened the window, and I added the last line. From what I can gather, the addition of that line tells my program where to look for updated DLL's upon building the project, and I had the wrong location before.
Other than that, I have no idea how this solution worked, but hopefully it can work for someone else. If anyone knows the logic behind this solution, please let me know so I can clarify my answer. Thanks to everyone who gave me suggestions to fix this!
Visual Studio 2019. The error was misleading in my case. After building one project at a time, I ran into the actual build error in one of the projects, which prevented that project from compiling and therefore caused the missing dll error. Once the issue was resolved, everything built properly.
I'm building a WPF app w/ Visual Studio 2015 (Update 3), and—at least by now, I'm not sure for how long this has been the case—every time I make a change and compile, I'll get a failed build w/ the error
6>CSC : error CS2001: Source file 'C:[...]\Obj\Debug\AnyCPU\GeneratedInternalTypeHelper.g.cs' could not be found.`
If I just build a second time, though, it works just fine.
This smells to me like a dependency on another file that is generated afterwards or something like that, but I haven't been able to find out what it is, a google search didn't net anything either, and neither did a search through my project what this file is used for in the first place (the name suggests its purpose, but I don't know where exactly it is used).
It might also be that the (group-policy-mandated) Anti-Virus is holding an exclusive lock on the file or its dependency for a moment too long, and VS stumbles over that, I think I remember a problem like this at my last job, but I'm not sure that is the case (and I can't simply disable the scanner for a check, it's completely locked down and I don't want to violate company policy for trying to circumvent it).
Any ideas? It's not critical since it's easy to work around, but it's annoying and I don't really want to check in the project like this in the end.
I had the same issue and i found why it happened (in my case).
Every project of our solution has the same output folder.
The file GeneratedInternalTypeHelper.g.cs was generated at the same place for each project.
The build order/dependencies were computed and Visual Studio found that some project could be build in parallel.
In Tools > Options > Project & Solutions > Build and Run you can find the option "Maximum number of parallel project builds.
After changed from 8(in my case) to 1, no more files generated at the same time :)
It is a little slower to compile but really less annoying than compile multiple times... \o/
An alternative solution is to add project dependencies in the solution for the projects you don't want to build in parallel.
With this you can keep the parallel project build for the other projects.
I have just chased down the same error. In my case it was caused by Git checkout inserting a "%20" into the folder name of the solution where a space was expected. Replacing "%20" with space fixed all these missing *.g.cs errors. Thought worth mentioning here.
I have a weird error showing up in my project when it is open in the VS2012 IDE. Everywhere where I make use of another referenced project it suddenly says "Type or Namespace name could not be found". And by "says", I mean it has the text underlined in red with the error when I hover over it. The intellisense doesn't work for that code. BUT (and here's the weird part), the errors do not show up in the error console and the project builds and runs fine.
I can even debug and step through the code and it works perfectly fine. So at runtime the project is referenced fine but at design time the IDE can't find it. This worked for the past 2 weeks, and only then suddenly went a little bonkers. It's really annoying because I am rubbish at coding without intellisense!
Has anybody ever seen anything like this or have any suggestions?
I had this. I referenced assemblies whose "Target Framework" were set to ".Net Framework 4" in the "Application" secion of the projects properties. I changed this to ".Net Framework 4.5" not just in the referenced assembly's project but also the project I was building and it worked. Give this a try.
I have found this is a known problem with VS2012. Check to see how you are building, 64 bit or 32 bit. It won't work with 64 bit but it will with 32 bit. It will say things are missing and design will not work, however the program will run fine. I have heard the new VS update that hasn't been released yet will fix it.
Manually delete all the references to the libraries of the other projects and re-add. Intellisense rebuilds whatever it needs at that point and doing this has helped me in the past.
Another source of this problem is a solution with multiple projects containing code for the same namespace. The compiler can handle this. Intellisense won’t.
Related to a couple other answers here, I had a "Data" project using a "Data" namespace. Built fine, but just started recently showing errors from intellisense (even though it continued building fine.) (VS 2015.)
I fixed this by changing my "Data" project and namespace to "MyCompany.Data".
Oddly, the problem didn't seem to show up until recently, but making the change did fix it. Presumably there was a conflict in namespace with another project or reference, which can build fine, but intellisense can't handle.
You can change this in the Application tab of Project properties. You can also open up an EDMX diagram, right click, choose model browser, choose the second collapsable item in the model browser tab, hit properties, and there you'll find the Namespace option for generated Entity Framework entities and contexts. (Similiarly, if you modify an Entity Framework Model's namespace, you might also need to change the related connection to match [in Web.Config for ASP.Net and MVC.])
Make sure that there is no class with the name same as Project default namespace.
make sure that you don't reference .net framework 4.5 projects in .net 4 projects!
Examine your .proj files in a text editor and make sure the paths to your references are correct.
This can also happen if you set the Build Action to "None" on the referenced file and forget about it.
I had the same problem, where it would build and run fine, it just would always show that error and I couldn't use intellisense with the class.
I actually used the automatic method of creating the class in a new file to resolve the issue, then just copied the code over from the real class. I deleted the old file, renamed the new file, and now it works.
I'm writing applications and libraries simultaneously, and whenever I update a library it's a bit hard to get it recognized in the consumer application. I have open a separate Visual Studio instance for each library and application. After rebuilding a library I get in the consumer applications the warning/error below. I then either have to remove the reference and add it again. Or I have to clean and build the library solution 3-4 times, for such warning/error to disappear in the consumer app VS solution. Why would doing that 4 times make any difference to doing it 1 or 2 times..?
Would like to understand why this happens and if something can be done to make this work more smoothly?
Not sure if it's relevant but most of my applications I write in VB.NET and libaries in C# (as I'm in progress of changing everything to C#). I also have C# files from the libraries open in the consumer application VS, as it pops up during debugging. I also reference library dlls in the library project /bin/Debug folder, because I'm making a lot of changes at this point of development.
Warning 1 Namespace or type specified in the Imports 'somelibrary'
doesn't contain any public member or cannot be found. Make sure the
namespace or the type is defined and contains at least one public
member. Make sure the imported element name doesn't use any
aliases. 'local path'
..
Error 72 Unable to load referenced library 'path\somelibrary.dll': The
process cannot access the file because it is being used by another
process.
I'm writing applications and libraries simultaneously, and whenever I update a library it's a bit hard to get it recognized in the consumer application. I have open a separate Visual Studio instances for each library and application.
This is the fundamental source of your problem. Visual Studio does not like it when things outside it's control change. You should have a single solution open with all the relevant projects included in it. Then when something changes, all the projects which depend on that project will automatically be rebuilt. (At least, that's the default.)
After rebuilding a library I get in the consumer applications the warning/error below. I then either have to remove the reference and add it again. Or I have to clean and build the library solution 3-4 times, for such warning/error to disappear in the consumer app VS solution. Why would doing that 4 times make any difference to doing it 1 or 2 times..?
I don't think it has anything to do with how many times you clean and rebuild it, but how long it's been since you last made a change - you have to wait long enough for the VS instance building the dll to release the lock on the file, before the VS instance that is using it is able to access it.
When you build a project you lock up the .DLL file in the project you build it from, because that is the version of the assembly that the library instance of visual studio will use - however you are referencing that very same library in another process hence the reason you are seeing the error.
You have two options, keep having two instances and then close the two instances open them again and it will be fine.
What you are better off doing is adding the project itself you are referencing (and are getting the error for) to your solution. Then instead of referencing YourProject/bin/debug/assembly.dll add a reference to the local project via the Projects tab. This will then keep one process referencing the appropriate assemblies that it needs.
For every project in the solution check the project settings -> Compile tab -> advanced compile options... -> target framework(all configurations), see if they are all (for example) .NET framework 4. having different or the wrong framework might cause the problems you're having right now
My problem seems to be relatively simple. I have a c# solution created in VS2010 with several projects with project references configured appropriately. I use MSBuild on our build machine which works fine, building in the correct order incrementally to be efficient. However, if I extend the interface (adding a public property etc.) and increment the AssemblyVersion of one of the projects that others depend on, it seems that MSBuild is unable to refresh the caching on down stream dependents and throws an error that it cannot find the previous version of the changed dll. Interestingly if I run the build again immediately afterwards, it tells me that the output hasn't changed and completes the build without error but I have no longer any confidence that it has done the right thing.
There is a file 'ResolveAssemblyReference.cache' that seems to hold the old reference and if I delete this from the obj/x86/Release folder before each build I never receive any errors but don't know if the output has/should have been rebuilt.
I would like to understand why MSBuild struggles with this and why on a second build it seems to report that the first build did actually work and that the targets are up to date.
Until I understand what is going on I am going to have to always force a rebuild of the entire solution to be certain I have compatible files.
Incidentally if I build in VS2010 I never seem to suffer this as I suspect it updates that cache appropriately each build.
Update:
I have found that my use of 'OutDir' on the command line for MSBuild seems to be to blame. If I remove this then the referencing seems to be resolved appropriately. However now I do not have my output copied to where I need it for deployment...