TFS Build Definition Templates - Set folder path

The snippet below is taken from a TFS build definition file.

<mtbwa:CopyDirectory Destination="[BuildDetail.DropLocation]" DisplayName="Copy Files to Drop Location" Source="[BinariesDirectory]..\Packages" />

Regarding the source attribute, I want to set the value to a particular folder destination, using an existing variable and then going up one level.

If the variable [BinariesDirectory] was equal to "C:\TFS\Binaries", I am trying to set the source to "C:\TFS\Packages", but it just 开发者_JAVA百科does not understand ..\ and will actually look for a folder at "C:\TFS\Binaries..\Packages"

How can I go up a folder level?

Thanks in advance

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Means that it elavates to parent folder, then submerge to PACKAGES

use double \