Thank you for your help! How do I reformate my USB?
Press the Shift key when you insert the USB
Then within windows explorer right click the USB drive and select format… Use full not quick
I don’t see the full formatting, only the quick… And I can’t tick the lowest box…
OK use the quick one initially and then scan the USB again with MCShield
Sorry to bother you again! he formatting worked, McShield says ‘no malware found’ so that’s good news. But when I put the usb, Windows tells me this:
No program has been linked to the file type, and I need to go to control panel so do sth, but I don’t understand what exactly…
I searched a bit on the internet and found this (Dutch) website for rearranging the keys and values:
http://sevenbits.nl/probleemoplossing/bestandsextensies_herstellen.html
“Schijven” are drivers, I downloaded it and ‘installed’ it, so the keys and values are added, but when I insert my USB again, the same default message reappears. Any idea what I should do?
Could you try this MSfixit please http://windows.microsoft.com/en-gb/windows-vista/tips-for-solving-problems-with-usb-devices
Solved! No troubleshooting messages anymore !
Everything clean, laptop as well as my USB device!
I’m running a additional scan through MalwareBytes just to be sure, but I don’t expect any malware anymore.
I really appreciate the time you took to help me with this issue and I really want to thank you for this, s well as Avast for this great forum where we can post our issues and can be helped very quickly!
Can I delete all the programs I have installed to detect the malware?
In that case methinks I will send you on your merry way 
Subject to no further problems
I will remove my tools now and give some recommendations, but, I would like you to run for 24 hours or so and come back if you have any problems
Now the best part of the day ----- Your log now appears clean 
A good workman always cleans up after himself so…The following will implement some cleanup procedures as well as reset System Restore points:
Remove ComboFix
[*]Hold down the Windows key + R on your keyboard. This will display the Run dialogue box
[*]In the Run box, type in ComboFix /Uninstall
(Notice the space between the “x” and “/”)
then click OK
http://i1224.photobucket.com/albums/ee362/Essexboy3/Misc%20screen%20shots/CF_Uninstall-1.jpg
[]Follow the prompts on the screen
[]A message should appear confirming that ComboFix was uninstalled
Download and run Delfix
https://dl.dropboxusercontent.com/u/73555776/delfix.JPG
: Keep Java Updated :
WARNING: Java is the #1 exploited program at this time. The Department of Homeland Security recommends that computer users disable Java
See this article and this article.
I would recommend that you completely uninstall Java unless you need it to run an important software.
In that instance I would recommend that you disable Java in your browsers until you need it for that software and then enable it. (See How to diasble Java in your web browser and How to unplug Java from the browser)
Now that you are clean, to help protect your computer in the future I recommend that you get the following free programmes:
CryptoPrevent install this programme to lock down and prevent crypto ransome ware
https://dl.dropboxusercontent.com/u/73555776/CryptoPrevent.JPG
Update and run weekly to keep your system clean
It is critical to have both a firewall and anti virus to protect your system and to keep them updated.
To learn more about how to protect yourself while on the internet read our little guide How did I get infected in the first place ?Keep safe 
Thank you for the tips! I’ve deleted the programs. Unfortunately, I need Java, but I’ll disable it in my browser.
Everything is clean, thanks to you!
My pleasure