SrtTrail.txt: What Startup Repair's Log Means and How to Fix the Boot

The fast answer. The path C:\Windows\System32\Logfiles\Srt\SrtTrail.txt on the "Automatic Repair couldn't repair your PC" screen is not the error itself — it is the diagnostic log that Startup Repair wrote when it failed. The underlying cause is usually corrupted system files, a bad update, or a damaged boot configuration. From Advanced options, open Command Prompt and repair system files offline (confirm the Windows drive letter with diskpart first — it may not be C: inside WinRE):

sfc /scannow /offbootdir=C:\ /offwindir=C:\Windows
chkdsk C: /f /r

If the error appeared right after a Windows Update, choose Uninstall Updates from Advanced options instead — that is the fastest, safest fix for update-triggered cases.

Why this happens

Corrupted system files — an unclean shutdown, power loss, or malware damaged boot-critical files. Windows runs Startup Repair automatically, Startup Repair fails, and writes its findings to SrtTrail.txt. This is the most common cause.
Failed or interrupted Windows Update — a partially applied update left the system in an inconsistent state that Startup Repair cannot resolve on its own.
Corrupt or incompatible driver — a third-party driver in the boot path (GPU, antivirus filter, VM tools) is damaged or incompatible. The log often names the specific file.
Boot record or BCD corruption — the Boot Configuration Data or master boot record was damaged, usually by an unclean shutdown during a write.
Disk errors — bad sectors on the drive prevent Windows from reading the files it needs to start.

Step-by-step fix

Step 1 — Get into Windows Recovery (WinRE)

Force three failed boots (power on, then hold the power button to kill it as the Windows logo appears, three times) and Windows opens Automatic Repair. Or boot from a Windows 10/11 install USB and choose Repair your computer. Then go to Troubleshoot → Advanced options.

Step 2 — Read the SrtTrail.txt log

Before running repairs, check what Startup Repair already found. In Advanced options → Command Prompt, confirm the Windows drive letter first:

diskpart
list volume
exit

Find the volume with the Windows installation and note its letter. Then open the log (substitute your drive letter for C:):

notepad C:\Windows\System32\Logfiles\Srt\SrtTrail.txt

Look for lines like "Boot critical file C:\Windows\System32\drivers\somedriver.sys is corrupt" or "Root cause found". If the log names a specific file, note the path — Step 7 covers how to handle it. If the log only says repairs failed with no specific file named, continue with the steps below.

Step 3 — If it started after an update, uninstall the update

In Advanced options, choose Uninstall Updates → Uninstall latest quality update. This reverses most update-triggered cases without touching your data. Reboot and test before doing anything else.

Step 4 — Run Startup Repair

In Advanced options, choose Startup Repair. It already failed once (that is why you see the SrtTrail.txt screen), but after a full power cycle it sometimes succeeds on the second pass. If it fails again, continue below.

Step 5 — Repair system files and check the disk

In Advanced options → Command Prompt, run SFC against the offline Windows installation and then check the disk (same drive-letter caveat as Step 2):

sfc /scannow /offbootdir=C:\ /offwindir=C:\Windows

chkdsk C: /f /r

chkdsk /r scans every sector and can take hours on a large or damaged drive — let it finish. Reboot and test.

Step 6 — Rebuild the boot configuration

If system files are clean but the boot records are damaged, rebuild them from the same Command Prompt:

bootrec /scanos
bootrec /rebuildbcd
bootrec /fixmbr
bootrec /fixboot

When bootrec /rebuildbcd finds a Windows installation, type Y to add it. Reboot and test.

UEFI/GPT note: on modern UEFI systems bootrec /fixboot can return "Access is denied" — that is normal and not the real fix on those machines. See the bcdboot procedure instead.

Step 7 — Handle a named corrupt driver

If Step 2 named a specific corrupt file (e.g. a .sys driver), rename it from the WinRE Command Prompt so Windows bypasses it on the next boot:

ren C:\Windows\System32\drivers\somefile.sys somefile.sys.bak

Replace the path and filename with whatever the log reported. Reboot. If Windows starts, uninstall the application or driver that owned the file and let Windows Update install a clean replacement. If the corrupt file is a core Windows component rather than a third-party driver, run sfc /scannow from an elevated prompt inside Windows to restore it from the component store.

Data safety: If the files on this machine matter and you don't have a backup, image the drive before you run repairs. SFC and bootrec are normally safe, but chkdsk /r stresses every sector and can push a weakening drive from readable to failed. Take a full sector image to a known-good external disk first, and never run repairs on the only copy of irreplaceable data.

GRAM tip: The fixes above run in Windows Recovery, which is already on the broken PC. Once the machine boots again, plug in GRAM — a free portable repair toolkit that runs from a USB inside Windows — to read the crash history, check the disk's SMART health, and let its AI agent confirm whether the root cause was a bad update, a corrupt driver, or disk errors so the problem doesn't come back.

Download GRAM free See AI pricing →

FAQ

Can I fix this without a second working computer?

Yes. You only need to reach Windows Recovery (WinRE), which lives on the broken PC itself — force three failed boots to trigger Automatic Repair, or boot from any Windows install USB. No second computer is required for the repair. (GRAM runs inside Windows rather than from boot media — use it once the machine boots to verify disk health and confirm the root cause.)

What does the SrtTrail.txt file actually contain?

It is a plain-text log of everything Startup Repair checked and tried: which boot-critical files it scanned, which ones failed integrity checks, and what repairs it attempted. The most useful line is usually near the end — look for "Boot critical file ... is corrupt" or "Root cause found" to identify the specific file that prevented Windows from loading.

Is it safe to delete SrtTrail.txt?

Yes, but it will not help. SrtTrail.txt is just a diagnostic log — deleting it does not fix the underlying problem that prevented Windows from booting. Startup Repair creates a new one on the next failed boot attempt. Focus on the repair steps above instead.

The log names a specific corrupt file — what do I do?

Rename the file from the WinRE Command Prompt (e.g. ren C:\Windows\System32\drivers\filename.sys filename.sys.bak) and reboot. If Windows starts, uninstall the application or driver that owned the file and let Windows Update install a clean copy. If the file is a core Windows system file rather than a third-party driver, run sfc /scannow from an elevated prompt inside Windows to restore it from the component store.