Fixing “Unable to load task handler … for task …” in VSTS/TFS 2015 build

26 Aug, 2016
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Last week I introduced a client to the new TFS 2015 build system. They happily started experimenting with it, but soon ran into a bit of a cryptic error message saying “Unable to load task handler … for task …”.


It turns out that the solution was pretty simple: the version of PowerShell that’s running on the build agent machine needs to be at least version 4.0. You can easily check this by typing “$PSVersionTable” in a PowerShell window. The “PSVersion” should read at least 4.0.


After upgrading the PowerShell version on the build machine, all was fine!

You can download the Windows Management Framework, which includes PowerShell, here:

I hope this helps!

Happy building!


Kees Verhaar
Welcome to my blog! I am an ALM consultant for Xpirit Netherlands B.V. Sounds fancy, doesn’t it? Basically it means I help people to do their work as a software engineer better, faster and easier. In the past couple of years of working in the field, I have encountered many things of which I thought: “I should share this!”. This blog is my way of doing that. You’ll find real life stories, tips & tricks, examples and probably even some code here. Hope you enjoy! If you have any suggestions, please feel free to drop me a line.

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