can not savely remove external hdd after using DT

[Angelhunter]

hey there

i found nothing in the forum about this..

Windows 7 Home Premium 64
DT 4.45.1.0236

Since I mount my imaged from an external HDD i can not remove it after this.
this is what i do:

plugin external hdd
start DT
add drive
mount image
do my stuff..
unmount image
delete drive
end DT

now i try to savely remove the external hdd .. but this is never working after using DT with it.
windows complains that something is still using this drive.

problem happens every time.

[Blazkowicz]

Did you try to kill explorer.exe in task manager and then try again?

[Angelhunter]

now that i just mounted an image and unmounted it right away it was working without any problem ... grrr
i will try killing explorer.exe next time it happens

[Terramex]

do my stuff..

Would you please elaborate on that ?

Is there by any chance another app e.g. synchronizing the drive ?

[Angelhunter]

killing the explorer.exe did not help.

what i do is just opening the ISO .. watch the movie or install something .. the unmount the ISO and remove the drive .. after this i can not securely disconnect the external HDD.
windows7 always says that some application is still using this drive.

i did nothing else with the HDD .. no synch, nothing .. i'm IT-support myself