I may have changed settings in disk management app wrong...Help

I have a Toshiba 750GB hard drive I know is in good shape, but when I was checking settings on it I noticed it had a large partition not used, so I set it as active and assigned a drive letter to it and now I cannot access the drive. I have purchased a new laptop and used a flash drive adapter to copy doc and pics to transfer to new one.  (Old laptop had bad m/board)

I am requesting help on the settings to see if I can get the info back...

I am attaching a jpg of the screenshot...It is drive 1

Thank you

Hi.  Can you recall what partitions were on it before you made the changes?  There are now only two partitions, a 686 GB data partition ("D:") which appears to be essentially empty, and a roughly 12 GB recovery partition (seems big for a recovery partition).  Was the 686 GB partition the one you intended to mark as "active"?  

Note active partitions are ones that contain your operating system boot files, and you shouldn't normally modify this (only one partition on a disk can be marked active).  Setting a partition as active and doing nothing else should not result in data loss, to my knowledge anyway.

I should have left it alone...the big partition I don't think should be active...my documents are on the small partition...

Are you sure you had documents on what is now labelled as the recovery partition (the 12 GB one)?  It just seems unlikely to me.  The recovery partition is generally used to contain the Windows Recovery Environment or a custom OEM partition which allows you to "factory reset" a computer back to it's original state.  These partitions do not normally have a drive letter assigned (they're hidden partitions) and in my experience, Windows Disk Manager does not let you assign a drive letter to these partitions.  It's possible to use the Diskpart command line tool to assign a letter - as demonstrated here Learn How to Unhide/Show Recovery Partition in Windows 10/8/7

To be honest, I'm not going to recommend making any changes myself as it just seems weird.  I'd wait for a second opinion.  Are you sure you didn't reformat a partition, or delete and create a new one to fill the space?  In which case it will likely need data recovery software to try to restore any lost files.

Thanks for the reply...I know I didn't reformat the drive.  This drive was in the laptop which had main board issues so I put it on a usb adapter and actually looked to see if the files were listed in file explorer..they were...now, when I put the drive and adapter on the new laptop they were not there...I do remember making the large partition active and assigned the dive letter...before I put it in the new laptop....can I revert it back to the way it was?

BTW..I ran hd test on the old drive first and it showed no errors

For reference

Using a live Linux distribution, like Linux Mint from a USB flash drive, is sound advice. It typically enables you to mount and access the contents of any partition that uses a recognized file system, whether it is designated as a recovery partition or not.

However, I have doubts that there will be any documents or user files stored in the 12 GB partition, for reasons I mentioned (I believe it to be a hidden OEM recovery partition).  But you can take a look.

Thank you both for responding and I will try the Linux and leave my results on this platform...BTW, I did not knowingly delete Windows or reformat the drive

Edited by geno368, 06 November 2024 - 06:01 PM.

I would see if you can assign a drive letter to the smaller partition. I've seen a 12GB rescue partition unless it was an OEM partition for a factory reset and that went away when Windows 10 came out.

You can make a partition not active using diskpart.

Edit: When you said "You could not access the drive" do you mean an error displayed in Windows saying access denied?

Edited by JohnC_21, 06 November 2024 - 06:49 PM.

no, John..I just meant I could not see any data like a did before

I have a very limited knowledge of using diskpart...steps???

Edited by geno368, 07 November 2024 - 12:53 AM.

Complicated all command line : https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/diskpart

Overview : https://learn.microsoft.com/en-us/windows-server/storage/disk-management/overview-of-disk-management

MS Help (not great) : https://support.microsoft.com/en-us/windows/help-in-disk-management-ad88ba19-f0d3-0809-7889-830f63e94405

Useful : https://www.windowscentral.com/how-clean-and-format-storage-drive-using-diskpart-windows-10

Long list of subjects with URL's from Howtogeek(.)com site : https://www.google.com/search?client=firefox-b-d&q=howtogeek.com+how+to+use+disk+managment   Very useful site on almost any subject of life or computers.

If your computer boots fine then I don't think changing the active partition to not active will make a difference. Will it let you assign a letter to the small partition?

Here are the steps for marking inactive. Make sure you use the correct disk #

https://kb.paragon-software.com/article/1136

Edited by JohnC_21, 07 November 2024 - 09:08 AM.