Hi Pavel,
Welcome to Microsoft Community and we are glad to assist you on this issue.
As per the query, it seems like Transcend 8GB USB 2.0 Jet Flash Drive TS8GJF300 does not work properly when connected to the computer.
Transcend 8GB USB 2.0 USB drive is compatible with Windows 8.
You can refer to the link to check for the compatibility using Windows compatibility center:
Since, it is an issue related to hardware device, let’s check if the hardware and device troubleshooter does resolves the issue.
You can follow the methods:
Method 1:
I would suggest you to run the hardware and device troubleshooter and check if it helps.
You can refer to the link to run the troubleshooter:
Follow the section “Run the Hardware and Devices troubleshooter”
http://windows.microsoft.com/en-US/windows-8/what-device-isnt-installed-properly
Method 2:
I would suggest you to uninstall and reinstall the USB drivers again. Check if it helps.
You may follow the steps:
a) Press Windows and x key together and select Device Manager.
b) Locate the Universal Serial Bus controller and expand it.
c) Right click on each USB driver and click on Uninstall.
d) Restart the computer.
After restarting the computer, all the USB drivers would be reinstalled automatically on the
computer.
If the issue still occurs, I would suggest you to check for the latest driver for the USB drive at Transcend website. You can refer to the link to check:
http://www.transcend-info.com/Support/index.asp?Func1No=3&LangNo=0
Hope it helps.
Feel free to contact us if you have any other Windows related issue and we would be glad to help
you.