Compilation failed when invoke workflow from subfolder

then for a test, try full…

That workts. This will work for now. I hope UiPath will fix this bug until I need to move the project.


This error is not linked to your workflow but it is caused by the compilation process. It seems sub-folders are not supported in library - although this limitation is not documented - although this is not unusual in UiPath :slight_smile: Hard to say if this is bug or feature :slight_smile:

If you check the output panel you will see there a warning in preprocess phase.

I did a quick test now:
I put WF1 and WF2 in a subfolder, WF1 invokes WF2 using relative path - compilation failed.
After removing the invoke of WF2 from WF1 the compilation finished.

@loginerror: Could you pls advise?


But when you run the library, it should not look for the workflows using the full path, so i hope…

I have been using libraries for a year and it has been working until this week.

I guess full path will not work in runtime. I have to test that.

Pls post here result of your testing.

My test showed that the library worked fine in runtime. I moved the code so there were no code where ‘Invoke Workflow file’ pointed at. Test was done from orchestrator and from studio.

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Hi @Brasse2873

Could you see if this documentation bit fixes your issue?

The workaround resolves the issue but -

What is the difference/advantages between the legacy library compiler and the modern library compiler other than the disadvantage of not being able to organize the XAMLs in it’s respective folders?

By using the legacy compiler, what impact does it have on the existing Jenkins build etc for CI/CD? Any changes required there as well? Please advise.

@Teja_G This issue is fixed in Studio 2019.10.4.
By using the new library compiler a library compile time should be faster, also the load time of compiled activities should be faster.
It shouldn’t have any impact on existing Jenkins builds for CI/CD unless you use “UiPath.ActivityCompiler.CommandLine.exe” in your builds. By default the command line application will compile a library using the legacy compiler unless you specify the flag ‘-useCSharpCompiler true’ to use the new compiler.

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TL:DR; The compiler compiles commented out code (disable activity), as a reason why publishing a library using 2019.10 throws errors the The given key was not present in the dictionary error message. hth

One note, if someone has somehow gotten to the bottom of this thread and is reading this without having a resolution. Not sure if this should be recorded as an issue or not, but in my case, my compilation issues were due to one file, having an invoke workflow activity to an external file system file. I know this isn’t legit when building a library, but what was interesting is that the invoke workflow activity was commented out. The only highlight here, whether it’s right or wrong to compile it, is that it’s different than previous versions. I don’t see anywhere in any of the comments of this specific scenario. The commented out code was there before i upgraded to 2019.10. Figured i’d share.

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That is interesting, it is good to comment so developers can look into this also. :slight_smile:


I am currently using UiPath Studio 2020.4.3 Enterprise and I am still facing the same issues. Is this bug still not fixed? Is this behavior fixed in any newer version? I really unlikely want to use one of the two supposed workarounds.

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Hi @Phipsll

Seeing that you are using an Enterprise version, I would suggest you to contact our technical support via this form:

It could be something specific to your project, but if it is indeed a bug, our support team will escalate the issue accordingly :slight_smile:

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@Phipsll Did you get a solution to the problem?
This bug is driving me insane

Hi @Konrad

If you are a an enterprise customer, I would suggest you to check with our technical support:

I think this might have been fixed in 20.10 (or even via updating of the packages to said version).

However, I think the issue from the above screenshot is not the one that was originally addressed in this topic. Based on the errors on the screenshot, I would make a guess that the XAML file that is being invoked contains and uses activities/namespaces that are not available in the currently opened project. I recall this used to be an issue when one would try to invoke a XAML file from another project that used different packages. A fix for that was to install the same packages in the parent project.

Hi @Konrad, I applied the workaround by using the legacy library compiler proposed of @loginerror because I did not have the time yet to contact the technical support. Just set the flag for the property UseLegacyLibraryCompiler to true. Afterwards the publishing of a library takes 10x longer but I can live with that.

Link to solution: Legacy Library Compiler Workaround

@Phipsll Alright, thank you for the answer :slight_smile:

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i run into the same issue as @Phipsll with Studio 2020.4.3.
A fix for this bug is not noted in the release notes of Studio 2020.4.4 / 2020.10.2.

@loginerror: Is this bug known to the UIPath development team / already fixed in a more recent version than 2020.4.3? I just wanted to check before creating a ticket.

Bug description:

Thanks. It looks like the issue is already on our roadmap and will be fixed in the future releases. I’ll try to update this topic when I will know more details.

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