Dell Inspiron 5748 hard freezes after Windows 10 Updates - possible Secure-Boot-Update issue

TECHNICAL REPORT

Persistent System Freezing on Dell Inspiron 5748 Running Windows 10

Prepared for technical support / Microsoft investigation

1. Executive Summary

This report documents a recurring hard-freeze problem affecting a Dell Inspiron 5748 when running Windows 10. The system can operate normally immediately after a clean installation, but the severe freezing problem returns after Microsoft Windows updates are installed. The failure is a complete system lock-up: the display remains frozen on the same image, normal keyboard commands do not respond, Ctrl+Alt+Delete does not work, and the computer cannot be recovered without holding the physical power button to force it off.

The problem has been reproduced after fresh Windows installations. The strongest pattern observed is that the laptop remains stable before Windows updates are applied and becomes unstable after Microsoft updates are installed. The user has also tested and replaced several hardware components and has performed driver, BIOS, Windows installation, and update-related troubleshooting.

2. Computer and Operating System

• Computer: Dell Inspiron 5748

• Operating system covered by this report: Windows 10

• Processor: Intel Core i7-4510U CPU @ 2.00 GHz

• Graphics: NVIDIA GeForce 840M, 2 GB, together with Intel HD Graphics

• RAM: 8 GB; RAM was replaced with new memory during troubleshooting

• Storage: New SSD installed

• BIOS: Dell BIOS A16, dated 09-02-2020, reported as the current BIOS

3. When the Problem Started

The problem began no later than approximately two months before the August 2026 troubleshooting period, and may have started approximately three months earlier. The user noticed a clear relationship between a fresh Windows installation and the subsequent installation of Microsoft Windows updates.

The issue is not simply an occasional application crash. It is a system-wide hard freeze that prevents normal operation and requires a forced shutdown.

4. Exact Symptoms

• The laptop initially works normally following a fresh Windows 10 installation.

• After Microsoft Windows updates are installed, the laptop can begin freezing after a short period of normal use.

• The freeze is a complete hard lock: the picture remains on screen and does not change.

• Keyboard input becomes unresponsive.

• Ctrl+Alt+Delete does not work during the freeze.

• The system cannot be recovered through normal Windows controls.

• The only effective recovery observed is to hold down the physical power button until the computer switches off.

• The issue is not described as a normal black-screen sleep problem; during the fault, the displayed image remains frozen.

5. Reproduction Pattern

The most important observation is the repeatable difference between a clean Windows installation and a system after Microsoft updates have been applied.

1. Perform a fresh installation of Windows 10.
2. Before Windows updates are installed, the laptop can operate normally.
3. Allow Microsoft Windows updates to install.
4. Restart as required by Windows.
5. After the updates have been installed, the severe freezing problem returns.
6. The freeze may occur after only a few minutes of operation.
7. Troubleshooting Already Performed

6.1 Fresh Windows installations

Windows was freshly installed multiple times in an attempt to rule out corruption or problems left over from a previous installation. The user reported performing fresh installations approximately five times. The same general pattern was observed: the machine was stable before the Microsoft Windows updates and became unstable after the updates.

6.2 Hardware checks and replacement

• A new SSD was installed.

• The RAM was replaced with new 8 GB memory.

• The user has observed no indication that overheating is causing the problem.

• The user has also investigated the graphics hardware and does not believe the graphics card is the cause.

6.3 BIOS investigation

Dell BIOS versions were checked. BIOS A13 and A15 were downloaded and attempted, but the system reported that those versions were older than the BIOS already installed. The laptop reports Dell BIOS A16 dated 09-02-2020. Therefore, there was no reason to downgrade the BIOS to A13 or A15.

6.4 Dell driver updates

Dell SupportAssist was installed and used to check and update the system drivers. The following updates were reported as installed through SupportAssist:

• Dell Touchpad driver

• Dell Wireless Wi-Fi driver

• Dell Security Advisor update

• Intel chipset driver

• Realtek audio driver

• Realtek card reader

• Realtek Ethernet controller

6.5 Microsoft Store application updates

Microsoft Store application updates were also installed separately. These application updates did not reproduce the same freezing problem. This is significant because the instability appears specifically associated with Windows system updates rather than ordinary Microsoft Store application updates.

6.6 Windows Update testing

The system was tested with Windows updates blocked/disabled after a fresh installation. While Microsoft Windows updates were prevented from installing, the laptop remained stable during testing. The machine was also used for extended periods, including YouTube/music playback, without reproducing the hard freeze.

The laptop was left idle and allowed to enter sleep mode. It subsequently woke normally. This indicates that sleep/wake operation itself was not consistently causing the problem when the system was in the stable, pre-update state.

7. Update-Related Incident

During one test, Microsoft updates including the Windows Malicious Software Removal Tool, a .NET Framework security update, Security Update KB5101650, and a Broadcom-related update were involved in the update process. Some updates were shown as pending restart and the computer was restarted. Following the restart/update process, the laptop froze again.

This incident further strengthened the observed correlation between Windows system updates and the return of the hard-freeze problem. It does not, by itself, prove that any single KB or driver is the sole cause.

8. Recovery / System Restore Attempt

System Restore was attempted as a possible way to return the computer to a stable state. Windows displayed a recovery message indicating that the device had encountered a problem and could not be repaired, with an instruction to press Enter to see other recovery options. The expected advanced-options button was not visible to the user. The recovery attempt was therefore not completed successfully.

9. Current Stable Configuration / Important Observation

After another fresh installation, Windows updates were blocked, Dell drivers were updated, and the BIOS was confirmed to be the current A16 version. Under this configuration the laptop was reported to be working normally and remaining stable.

This provides an important diagnostic comparison: the same physical laptop, with a new SSD and new RAM and with updated Dell drivers, can operate normally when Windows system updates are not installed. The severe freeze returns when the Windows update process is allowed to install the relevant system updates.

10. Technical Significance

• The fault is repeatable rather than a single isolated crash.

• The problem has survived multiple clean Windows installations.

• The issue occurs on the same physical laptop despite a new SSD and replacement RAM.

• Dell SupportAssist driver updates did not cause the same hard-freeze behavior.

• Microsoft Store application updates did not cause the same hard-freeze behavior.

• The laptop can remain stable for extended periods when Microsoft Windows system updates are blocked.

• The problem returns after Windows system updates are installed.

• The freeze is severe enough that Windows cannot be controlled through normal keyboard or recovery commands at the time of failure.

11. New Diagnostic Finding – Secure Boot Update Scheduled Task

On 30 August 2026, an additional read-only diagnostic check was performed. Task Scheduler was opened and the folder \Microsoft\Windows\PI was inspected. The Microsoft scheduled task named “Secure-Boot-Update” was present, enabled, and in Ready status.

Observed task details:

• Task name: Secure-Boot-Update

• Location: \Microsoft\Windows\PI

• Author: Microsoft Corporation

• Description: “This task updates the Secure Boot variables.”

• Trigger: At system startup; after being triggered, repeat every 12 hours indefinitely.

• At the time of inspection, the task showed a successful last-run result (0x0).

A separate read-only check using System Information (msinfo32) confirmed that the Dell Inspiron 5748 uses UEFI firmware mode and that Secure Boot is enabled. The BIOS remains Dell A16 dated 02-09-2020.

12. Possible Relevance of June 2026 Secure Boot Update Reports

During investigation, recent Microsoft Community material was identified describing Windows 10 systems that freeze shortly after startup following Windows updates. One June 2026 discussion described a very similar symptom pattern: the computer freezes a few minutes after login after a Windows 10 update. The discussion included references to the Microsoft\Windows\PI\Secure-Boot-Update scheduled task, and a separate response specifically directed Dell users to a discussion concerning a June 2026 Secure Boot update.

These reports do not prove that Secure-Boot-Update is the root cause on this Dell Inspiron 5748. They are included because the same Microsoft scheduled task is present and active on this computer, Secure Boot is enabled, and the observed freeze pattern after Windows updates is similar. Microsoft is requested to determine whether Secure Boot certificate/variable servicing, firmware compatibility, or another component delivered through Windows Update could be contributing to the hard freezes.

No Secure Boot setting or scheduled task was changed during this diagnostic check. The Secure-Boot-Update task was not disabled, Secure Boot was not turned off, and Windows Update was not re-enabled merely to reproduce the fault, because the current stable configuration was intentionally preserved.

13. Live Kernel Report Check

The folder C:\Windows\LiveKernelReports was checked for diagnostic dump files. The folder existed but was empty at the time of inspection. Therefore, no Watchdog or other LiveKernelReports dump file was available for analysis from the current installation. This is consistent with the current system remaining stable while Windows system updates are blocked.

14. Request for Microsoft / Technical Support Investigation

The user would like Microsoft or an appropriate technical support team to investigate whether a Windows 10 update, Windows driver delivered through Windows Update, compatibility change, or another Microsoft-supplied component introduced a condition that can cause a Dell Inspiron 5748 with the hardware described above to hard-freeze.

The user is specifically requesting confirmation of whether there is a known issue affecting this class of older Dell hardware on Windows 10, whether a particular Windows update or driver is implicated, and whether a permanent fix, rollback, replacement driver, or other supported solution is available.

15. Evidence and Information That Can Be Supplied

• Task Scheduler evidence showing Microsoft\Windows\PI\Secure-Boot-Update present, enabled, and Ready.

• System Information evidence showing UEFI mode and Secure Boot State: On.

• LiveKernelReports check showing no diagnostic dump files in the current stable installation.

• The Dell Inspiron 5748 model and hardware specifications.

• The BIOS version and date (Dell A16, 09-02-2020).

• The sequence of fresh Windows installations and update testing.

• The observed behavior before and after Windows updates.

• The list of Dell SupportAssist driver updates installed during troubleshooting.

• The Windows update incident involving KB5101650, .NET Framework security updating, the Windows Malicious Software Removal Tool, and a Broadcom-related update.

• The fact that the machine can remain stable when Windows system updates are blocked.

16. Conclusion

Based on the troubleshooting performed, the strongest reproducible evidence points to a software/update-related compatibility problem rather than a simple Windows installation failure or an obvious storage, memory, overheating, or sleep-mode problem. The repeated return of the hard freeze after Windows system updates, together with stable operation when those updates are blocked, makes this a suitable case for investigation of Windows Update components and Microsoft-provided drivers.

No conclusion in this report identifies one specific update as the confirmed root cause. The purpose of the report is to document the repeatable behavior accurately so that Microsoft or Dell technical support can investigate the relevant update, driver, compatibility, or kernel-level issue.

17. Short Problem Statement for Support Forms

Dell Inspiron 5748 running Windows 10 repeatedly hard-freezes after Microsoft Windows system updates are installed. The display remains frozen, keyboard input and Ctrl+Alt+Delete do not respond, and the laptop requires a forced power-off. Multiple clean Windows installations produced the same pattern. The laptop remains stable when Windows system updates are blocked, including during extended use and sleep/wake testing. The SSD and RAM have been replaced, Dell drivers were updated using SupportAssist, and the BIOS is already Dell A16 dated 09-02-2020. Please investigate whether a Windows 10 update or Microsoft-supplied driver/compatibility change is responsible and advise on a permanent fix. Additional diagnostics confirmed that Secure Boot is enabled in UEFI mode and that the Microsoft \Microsoft\Windows\PI\Secure-Boot-Update scheduled task is present and active. Similar June 2026 Windows 10/Dell reports referenced this Secure Boot update mechanism. This is a possible lead only, not a confirmed root cause, and Microsoft is asked to investigate the connection.