Invalid File Name

Hi all, i have a system with Win7 Ultimate 64 Bit, i have a Hard Disk drive C: and D: (Partition) and two external disk (portable of WD and a My Book Elite WD) …
i have install Comodo Bck, but when i must choose the folder where save my data i receive this error:

I have try on C:, D:, and the two external disk but i receive the same message … how i can resolve it???

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Please see the attachment.
You must type a name in the “Save as” box.


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:BNC tnx work right now!!!