USB-Modemstick-Cannot reinstall

[europanorama]

On one of my two HHDs I have major problem reinstalling my USB-Internet-Modem again. Systemrecovery does not work. Maybe only an older image could help which i want to avoid.
I must have to do with the used letters. Or drives which are not in the systemrecovery-list. Maybe the drive-letters of my external drives have been changed and are now mixed up. I tried to put them in the right order, didnt help.
I am using a second drive- plus external drive which are not active all the time, sometimes disconnected.

When this usb-stick is mounted again, briefly drive-letter J is popping up but i cant see the drive on "my computer". It is normally shown as CD.

Maybe this reinstallation problem started only when i deleted all Globetrotter Connect-words in registry.

I have two internet-solutions, one with stick, second one with huawei-modem(internet/phone).
I am switching whenever i reach the max. GBs.
I am deeply thankful for any hint.

[europanorama]

When i tried to uninstall modem-software it was sticking at "another 21 secs", After that i deleted entries named "Globetrotter Connect"-my internet service through this usb-stick.

lately i checked "computerverwaltung"-Datenträgerverwaltung(drives-organization or whatever it is named). checked this during attaching the stick.
An like on my computer i could temporarily see this drive popping up, as drive J.

I then changed drive letters of external drives. and now nothing is showing up anymore when reattaching this usb-stick-modem.

meanwhile i removed two trojans-trojan-dropper inside two programs of my external drive. one of this was installed and is now removed.

STILL UNSOLVED PROBLEM
Cannot attach/reinstall my usb-modem.


It is working on my second HDD.
Thank you very much and a quite sunday.

[europanorama]

Maybe the provider changed behaviour of my usb-modem. I had to exchange it last year. It does an autoinstallation.
What i did? Maybe this helped to solve my problem:

saved registry by exporting it. set a system-recovery-point.
uninstalled all usb-controllers. deactivated usb in cmos-setup temporarily. reinstalled usb-s3-driver of nvidia.
Then reconfigurated all drives, incl. cardreader(has four letters, two i had deactivated.

I still could see my usb-modem-stick flashing up quickly but disappeared.

I was very surprised seeing that the program reinstalled automatically.