c drive not seen by UEFI

[mindnightmix]

Envy x360 -15-bp143cl

Product Number: 3TS71UA#ABA

Windows 11 64.

had a 256 Toshiba M.2 2280, worked fine, updated to 512 M.2 2280 then could not create new folder anywhere. Updated the bios from 4.0 to 5.2. User Deep_World responded with questions but I cant get them. I says I'm not allowed. the laptop will start in Legacy not in UEFI. I have ran all the tests and they have all passed.

any help, I apologize for not knowing how to use the community. 

[VikramTheGreat]

Hi @mindnightmix,

Welcome to the HP Support Community.
 

Thank you for posting your query. I will be glad to help you.

Welcome to the HP Community, and no worries at all about using the forum. You're in the right place, and we'll do our best to help. From what you've described, the issue started after replacing the original 256 GB Toshiba M.2 2280 SSD with a 512 GB M.2 2280 SSD. It's good to know that the HP Hardware Diagnostics passed, as that indicates the notebook is detecting the SSD correctly and there are no obvious hardware issues.
 

Based on the information you've shared, my first suspicion is that the new SSD was cloned or installed using an MBR partition layout, which could explain why the notebook only boots in Legacy mode. The inability to create new folders, however, is more likely related to Windows file system corruption or an issue introduced during the drive migration, rather than a fault with the SSD itself or the BIOS.

To help us narrow this down, could you let us know:

• What is the manufacturer and exact model of the new 512 GB M.2 SSD? 
• Did you clone the original SSD or perform a clean installation of Windows 11? 
• When you switch the BIOS to UEFI, what exactly happens? Do you receive a Boot Device Not Found message, or does Windows simply fail to start? 

In the meantime, let's check a few things.
1. Verify whether the SSD is GPT or MBR

• Press Windows + X and open Disk Management. 
• Right-click the disk label (Disk 0) and select Properties. 
• Under the Volumes tab, check the Partition Style. 
  • GUID Partition Table (GPT) is required for UEFI boot. The 
  • Master Boot Record (MBR) explains why the notebook only boots in Legacy mode. 

2. Check Windows for file system corruption
Open Command Prompt as Administrator and run: sfc /scannow

Once that completes, run: DISM /Online /Cleanup-Image /RestoreHealth

Restart the notebook after both commands finish and check whether you're able to create a new folder.

3. Check folder permissions
Try creating a new folder in different locations, such as:

• Desktop 
• Documents 
• A folder on the C: drive that you created yourself 

If the issue occurs everywhere, it's more likely a Windows or file system issue rather than a permissions problem with a specific folder.

Based on everything you've shared so far, my first suspicion is that the new SSD was installed or cloned using an MBR partition layout, which would explain why the notebook only boots in Legacy mode. The folder creation issue, however, points more toward Windows itself, either file system corruption or an issue introduced during the migration to the new drive, rather than the SSD hardware or BIOS.

I hope this helps.

Take care and have an amazing day!