Notice (2018-05-24): bugzilla.xamarin.com is now in
Please join us on
Visual Studio Developer Community and in the
Mono organizations on
GitHub to continue tracking issues. Bugzilla will remain
available for reference in read-only mode. We will continue to work
on open Bugzilla bugs, copy them to the new locations
as needed for follow-up, and add the new items under Related
Our sincere thanks to everyone who has contributed on this bug
tracker over the years. Thanks also for your understanding as we
make these adjustments and improvements for the future.
Please create a new report on
Developer Community or GitHub with
your current version information, steps to reproduce, and relevant error
messages or log files if you are hitting an issue that looks similar to
this resolved bug and you do not yet see a matching new report.
After updating Xamarin and Xamarin.Forms to 126.96.36.199, each compilation attempt was leading to this error:
...\portable-win+net45+wp80+win81+wpa81+MonoAndroid10+Xamarin.iOS10+xamarinmac20\Xamarin.Forms.targets(68,4): error MSB4064: The "DebugType" parameter is not supported by the "XamlCTask" task. Verify the parameter exists on the task, and it is a settable public instance property.
...\portable-win+net45+wp80+win81+wpa81+MonoAndroid10+Xamarin.iOS10+xamarinmac20\Xamarin.Forms.targets(62,3): error MSB4063: The "XamlCTask" task could not be initialized with its input parameters.
Removing the line "DebugType = "$(DebugType)" " from Xamarin.Forms.targets allowed the app to compile and run again.
Looks like the DebugType parameter was left in Xamarin.Forms.targets by mistake?
this can have multiple causes:
- you updated XF but haven't reloaded the solution (restart your IDE)
- some projects in your solution points to different versions of Xamarin.Forms.
if the problem persists, please reopen the issue, and attach a solution causing the issue
*** Bug 56579 has been marked as a duplicate of this bug. ***
This is still a problem, even after verifying everthing points to the same version, cleaning, closing VS, deleting all bin and obj directories, and reopening solution in VS. Typical poor quaity of released versions fom the Xamarin Forms team. Come on guys. This is rediculous. You are supposed to be professionals.
@firstname.lastname@example.org please provide a solution demonstrating this issue.
Same for @email@example.com. please provide a reproduction so we can investigate
What information would be useful for you to be able to investigate further?
Here is some:
Visual Studio Enterprise 2015 V 14.0.25431.01 Update 3
The project which would not compile was created more than a year ago.
It is a PCL project, not using XAML.
After updating Xamarin a month ago, it was impossible to compile the andoid app.
"MSB4064: The "DebugType" parameter is not supported by the "XamlCTask" task."
We need a solution/project we can run, either that project or one that you are able to share that demonstrates the issue. You may also share it privately with us if there is a concern, and/or we can pursue an NDA so you can share it.
Some tips to make the upload smaller:
- do a clean/obliterate on the solution to remove bin and obj folders
- don't include the packages folder
Confidentiality concerns forbid me to share the exact project on which this occured.
I'll try to find some time to reproduce the issue in a dummy/simple Xamarin.Forms project and then share it with you.
As the reporter can't provide a repro, I'm re-closing this.
Feel free to reopen if/when you have a valid reproduction project triggering the issue.
I am experiencing the same problem as the reporter.
But it's very random and not reproducible.
Since many people are experiencing this bug it is there. Therefore I would not close it unless someone can provide some more information or a fix
This issue is definitely not closed. It happens all the time but is hard to reproduce when you want it. Just work normally on a project and it'll pop up. Very annoying. What I found works is just deleting all the bin/obj files of the projects (not CLEAN as that doesn't help) and build. Which should prove that it's *not* mismatched versions or something else 'we' did wrong; it's a Xamarin bug as the solution works fine most of the time. Not sure others are using it as well, but for me it happens only in PCL projects.
We need a project that suffers from this issue so we can confirm and address it. If you have one, please post it here or contact me directly to share it. firstname.lastname@example.org
I will try to make one, give me the weekend and I will either post it somewhere or I will, in confidence, send you the one I am working on. The only way I can work longer stretched of the time without restarting VS is by removing DebugType from .targets at this moment which someone in the Xamarin forums suggested as 'bandaid solution'. I will try to get a project to act up this weekend and will just send it straight to you as a zip including all bin/obj dirs.
if removing DebugType from .target fixes it for you, it means that sometimes, for some reason, a Xamarin.Forms.Build.Tasks.dll is loaded instead of the latest one.
so my money is still on your project referencing, directly or indirectly, multiple versions of that assembly, coming from different nuget packages.
of course, it could be something else...
I could not find anything of that, I will look closer. I am trying to reproduce in a clean project now.
However, if it's mismatched versions somehow, it would be nice if we can have some warning + quick fixer dialog for that as many people (only in our office this happens a lot and generally on the web the past months as well) seem to have a lot of dependency versioning issues with Xamarin. Some 'mismatched version in dependencies found, fix yes/no?' would be better.
Here's my scenario and environment.
Development Machine MAC OS, running Visual Studio for Mac 7.0.1 Build 24
"Local" builds using solution which contains a:
PCL Project (Common Models, ViewModel, Views etc) .Net Profile 111. (.Net Standard 2.0 causes other issues)
Common.Service .Net (Reference PCL and is consumed by Webservice) - Targeting .Net 4.5.2
iOS (Xamarin.iOS project)
"Local" project builds fine and consistently. Latest version of Xcode latest version of the .Net framework
"Build Agent" is also the same MAC, leveraging Mobile Center Build services calling into Remote Agent.
This build fails every time. Seems to be build and Build Task related, not IDE related. Please keep this issue open.
"/Users/ci/agent/vstsagent/_work/1/s/iOS.sln" (Rebuild target) (1) ->
"/Users/ci/agent/vstsagent/_work/1/s/iOS/iOS.csproj" (Rebuild target) (2) ->
"/Users/ci/agent/vstsagent/_work/1/s/iOS.Services/iOS.Services.csproj" (default target) (4:3) ->
(XamlC target) ->
/Users/ci/agent/vstsagent/_work/1/s/packages/Xamarin.Forms.188.8.131.52/build/portable-win+net45+wp80+win81+wpa81+MonoAndroid10+Xamarin.iOS10+xamarinmac20/Xamarin.Forms.targets(68,4): error MSB4064: The "DebugType" parameter is not supported by the "XamlCTask" task. Verify the parameter exists on the task, and it is a settable public instance property. [/Users/ci/agent/vstsagent/_work/1/s/iOS.Services/iOS.Services.csproj]
/Users/ci/agent/vstsagent/_work/1/s/packages/Xamarin.Forms.184.108.40.206/build/portable-win+net45+wp80+win81+wpa81+MonoAndroid10+Xamarin.iOS10+xamarinmac20/Xamarin.Forms.targets(62,3): error MSB4063: The "XamlCTask" task could not be initialized with its input parameters. [/Users/ci/agent/vstsagent/_work/1/s/iOS.Services/iOS.Services.csproj]
Was able to identify the Xamarin.Forms.220.127.116.11 NuGet Packages were not checked into the Git Repository. It was available locally, but not in Source Control. Hopefully this helps others.
For me this issue is only happening on my PC using VS2015 with Xamarin.Forms.18.104.22.168. 0 projects in my solution will build.
After much cleaning, obliterating etc. the ONLY fix was to revert to Xamarin.Forms.22.214.171.124
I tried many solutions with deleting bin & obj folder, clean, rebuild, changing build configurations etc. but the only reliable workaround for me is to close and reopen Visual Studio for Mac and if that doesn't help then I restart my Mac.
I still don't have a project I can send over, but I can make it happen now reliably; just take any 'old' (1 year) project and update the NuGet packages of the project to the latest, then compile. It happens that way for me every single time. I removed the flag from the targets file now in over 40 projects the past days and everyone I know now has complained about this. Hope this helps in fixing it... I'll continue to try to find a small project I can send that has it.
This iss a reaction on the email of DavidOrtinau on 30th of june about this issue. I have this issue in a Visual Studio solution containing:
- Portable project
- Android project
- iOS project
- 2 other portable library projects (referenced by the portable project)
- 2 Unit Test Android projects
- 1 WinForms project
The Android, iOS and portable projects have Xamarin.Forms referenced via NuGet and all use version 126.96.36.199.
This issue as described in this report re-appears frequently. It seems to occur when the time between compiles is more than around 30 minutes or after a large code change or a change within the references libraries and the main project. I cannot reproduce it, even when I tried to. I had the problem today 3 times today between 08:30 and 13:00(= time of writing).
When it occurs it CANNOT be solved by rebuilding or cleaning the solution or projects. The only way to solve it is to restart Visual Studio 2017 WITHOUT rebuilding or solution cleaning.
Hey, all. I'm new to Bugzilla (and relatively-new to Xamarin) so forgive me if I'm posting anything irrelevant... but I think I found a Forms solution in which the errors seem to be occurring regularly: https://github.com/xamarin/xamarin-forms-samples/tree/master/Navigation/TabbedPage.
I can verify I'm also running Visual Studio 2017 Community, on the Mac, with the Xamarin.Forms NuGet package at version 188.8.131.52.
Please clean the project, delete the bin/obj folders, and zip up the solution files minus the packages directory. Then post that here. The GitHub version doesn't use 184.108.40.206, so we want to inspect all your projects and config.
Also, in Visual Studio go to About > Show Details and copy all that info into a Gist for us.
For me a simple repro is to grab https://github.com/onovotny/SampleXamFormsWithNetStandard from Github.
Open up in VS Mac Preview, Alpha Channel, 7.2 Preview (Build 478). I immediately get the "XAMLC..." error when trying to compile.
After cleaning up /bin and /obj I get:
AppDelegate.cs(14,48,14,55): error CS0400: The type or namespace name 'Xamarin' could not be found in the global namespace (are you missing an assembly reference?)
AppDelegate.cs(23,30,23,47): error CS0115: 'AppDelegate.FinishedLaunching(UIApplication, NSDictionary)': no suitable method found to override
VS 2017 - No errors.
After frustration with this same issue, I finally found that in some project files (.csproj) there was a left over Import of the previous version of Xamarin.Forms
Cleaned this up, deleted all obj/bin folders, all good now.
As we have had no further reports for a month, we believe this is no longer an issue as of the latest stable build of Forms and VS. Please reopen with updated projects if the issue is still being experienced on the newer versions.
This is still very much a problem. We are on Xamarin.Forms 220.127.116.11863. This happens often and for multiple developers on the same project. It often helps to close the solution and open it again.
@Nicolai: please open a different ticket with a project we can use to reproduce the issue