When previous versions of the SoftGrid Client are originally installed via GPO, a subsequent upgrade to the SoftGrid 4.2 may fail with 1642, 1606 and 1603 installer errors.  On the client you may also see the following error:

The SoftGrid Client could not be started.
An unexpected error was encountered. Please report the following error code to your System Administrator.
Error code: xxxxxx-xxxxxx 12-00006002

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