I have exactly the same problem. What kind of information do you need to reproduce?
I am using a German locale on an English installation of Win10. Could it be a locale problem?
Running Jenkins as service as normal user.
Using latest Jenkins version 2.89.2, mstest is at 0.23.
My tests use a base class and [ClassInitialize] methods. [TestInitialize] methods is implemented in base class. Could this setup cause a problem?
This result file looks odd to me. Should the times not be in seconds? My tests take definitely longer than 0, 0.05 and 0.3.
d:\Program Files (x86)\Jenkins\jobs\test-project\builds\77\junitResult.xml
<?xml version='1.0' encoding='UTF-8'?>
What could I do to help debugging the problem? Is there a log which would help? Where?