1.    04 Jul 2017 #1
    Join Date : Aug 2016
    Posts : 373
    Windows 10 64 bit, 1703

    Drive letters change when multiple drives plugged in.


    My main external backup drive was assigned to drive letter G:. Upon plugging two usb drives in today that drive's letter got changed from G: to H: Why does that happen?

    Because that drive is used for Macrium daily backups assigned as G: in the backup definition the backup did not run.
      My ComputerSystem Spec
  2.    04 Jul 2017 #2
    Join Date : Jan 2015
    UK, Midlands
    Posts : 11,001
    Win 10 Pro (1703)

    Hi, if you assign the same drive letter to two different USB drives, one will get lost. Windows can only remember one letter per drive, assuming you've assigned it in Disk Management.

    So it's simple- keep them unique.

    (Great you're using disk imaging!)
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  3.    04 Jul 2017 #3
    Join Date : Aug 2016
    Posts : 373
    Windows 10 64 bit, 1703
    Thread Starter

    Hi Dalchina,

    Does that mean Windows max drive letter assignment is up to H? I currently have C: D: E: F: G: H:

    It appears to me that one of my usb drives stole drive letter G: from the backup drive

    Yes disk imaging is must, especially with this spate of ransomware although I'd hope not to pick that up in the first place!
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  4.    04 Jul 2017 #4
    Join Date : Jan 2015
    UK, Midlands
    Posts : 11,001
    Win 10 Pro (1703)

    No, example:

    USB A - you allocate letter R
    USB B - you also allocate R

    If you plug A in after B , A will lose its allocated letter.
      My ComputerSystem Spec
  5.    04 Jul 2017 #5
    Join Date : Feb 2016
    Phoenix, AZ
    Posts : 243
    Windows 10 Pro 1709 16299.19

    What you need to do is start assigning your external hard drives starting with Z:. It will always be remembered. If you have another external hard drive, assign it with Y:, etc. As far as your thumb drives, unless you have an application that uses your thumb drive and requires a specific drive address, assign it the next lower drive address, otherwise just let the system assign the next available drive address.
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  6.    04 Jul 2017 #6
    Join Date : Aug 2014
    Forever West
    Posts : 3,922
    Win10 Home and Pro, Win10 Insider Preview, Win7 Home, Linux Mint

    These are relatively old posts but may help:
    Microsoft Corporation

    http://www.tomshardware.com/answers/...e-letters.html

    One thing I do with all my drives is give them a unique Label [name], helps me identify them in two ways.
    Click image for larger version. 

Name:	Drives2.png 
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ID:	142426

    C: and D: are 2 partitions on the only internal HDD [1TB total]
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  7.    04 Jul 2017 #7
    Join Date : Jul 2015
    Posts : 9,394
    Windows 10 Pro

    Quote Originally Posted by Berton View Post
    These are relatively old posts but may help:
    Microsoft Corporation

    http://www.tomshardware.com/answers/...e-letters.html

    One thing I do with all my drives is give them a unique Label [name], helps me identify them in two ways.
    Click image for larger version. 

Name:	Drives2.png 
Views:	3 
Size:	29.4 KB 
ID:	142426

    C: and D: are 2 partitions on the only internal HDD [1TB total]
    But that won't help with Macrium Reflect because you can't set Macrium Reflect to save the backup images onto labelled partitions, you can only set it to drive letters. So if he labels his partition of backups as "Backups" - and it moves from G: to H:, the Macrium backup routine will still fail to run. It will be easier for the OP to see where the Backups drive is, but not Macrium Reflect.
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  8.    15 Jul 2017 #8
    Join Date : Aug 2016
    Posts : 373
    Windows 10 64 bit, 1703
    Thread Starter

    I haven't forgot about this thread...
    @storageman So if drive letters aren't manually assigned Windows will auto assign each time correct? How then does it sometimes assign the same drive letter to drives even after unplugging and re-plugging them?

    If Windows has already assigned a drive letter do I still have to manually assign that letter to the drive so it's not forgotten?

    Most of my drives default labels are easy enough to keep track of. Backup drive is a Seagate Expansion Drive and it's easy to know this is the backup drive.

    @NavyLCDR That's handy to remember for Macrium Reflect.
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  9.    15 Jul 2017 #9
    Join Date : Feb 2016
    Phoenix, AZ
    Posts : 243
    Windows 10 Pro 1709 16299.19

    If the drive has never been assigned a Drive letter, then windows will select the next available letter when you plug in that drive. For example - My system has a "C" drive (OS only), a "D" drive (Data only), a "E" (Dvd burner), if I plug in a device that never was assigned a drive letter, it will always be assigned "F" as long as nothing else is residing there, when it is plugged in. If I remove the device in "F" and then plug it back in, it will be assigned to "F".

    I have 9 external hard drives for backups. They start with "Z" thru "R". For this system, the "U" drive is always used for Macrium Backups. I have set up Macrium to always backup to "U". Multiple backups are kept in separate directories on "U". Depending on which sub directory I'm using for backups at this time, I have separate Batch files that are used. I always keep more than 2 backup sets + I also keep backups of the backups on "R". I have batch files set up to copy the backup sets from "U" to "R". Note that the directory structure is the same on every one of these backup disks. Since I have multiple W10 systems, they also use the same structure as this system does, but they each use different drive letters.

    Hope that clears it up.
      My ComputersSystem Spec

 


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