Dear Sir;
1. Navigate to Computer Management
2. Select Disk Management
3. In the bottom list locate the disk corresponding to the drive letters that you know don't map to anything
4. Right click identified Disk
5. Select Change Drive Letter option
6. On the resulting dialog click Remove
7. Click Yes on the resulting prompt
8. Repeat for other drive letters
btw does your Internet Dongle got memory in it? like some provide storage option too. https://superuser.com/questions/781844/why-mobile-internet-sticks-have-a-microsd-slot
Try to remove that microSD card and try activation.
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