Hi, Use Panda Usb Vacccine to inject from Panda.com..Or by majorgeeks.com. These are reliable sites for downloading. Due to virus or generic virus, this ejection problem crops up. When you normally insert a drive, it gets automatically connected and it tries to execute the autorun of any hidden files.
You could check pendrive for virus. You could enable showing all files in the view menu in the folder options. But when you try to delete the unwanted folders, it will not allow you to do so, because the the prgoram or virus exetuable is using the computer default processes during the time and hence, it is used by other process.
Once installed, click panda usbvaccine.exe and it will create a autorun.inf , file in the root of the pendrive. There are two options of injection. Computer and pendrive. First you vaccinate the computer and then the pen drive. Even though virus is in your computer further damage could be stopped by this action.
By vaccinating the pendrive, you could easily stop the process access of trojan, autorun suspicious programs from contacting the process from your computer. Now any folder could be deleted in the pen drive to get rid of these viruses or PUPs. You could delete the folders which deny access earlier. Once it is vaccinated, then it will not pass on the virus to other computers and your computer will not get affected by these hidden autoruns. Ok. Whenever you insert other pdrive then, it automatically injected it. Use and tell your experience. I am a long user of this wonderful free programme
http://www.pandasecurity.com/homeusers/downloads/usbvaccine/