Error messages are different when running on en-GB Windows 8.

I tried running the tests on my machine and noticed that some of the unit tests failed because the actual error messages are different from the expected.

I am not sure whether this is an operating system version difference or because I am running the en-GB UI.

This fix simply allows both versions of the error message. Alternatively, perhaps we should check for an error code?

My O/S version is:
* Microsoft Windows 8 Enterprise
* 6.2.9200 N/A Build 9200