Do not display invalid string data for system Information improperly captured in a VM

[JeremyMain]

Some of the system queries are not returning usable data that is being saved in the GPD file. The collection point is where the prevention of writing information that has not been collected is the first part of a fix, but with a large number of GPDs already generated, detecting the invalid characters is a good fix for existing data.

[JeremyMain]

Fix completed and to be included in v1.07b