How to Fix “The Semaphore Timeout Period Has Expired” (Error 0x80070079)

Windows returns Error code 0x80070079 – “The semaphore timeout period has expired” when a data-transfer operation does not receive the expected response within the time allotted by the storage or network subsystem.

This error message appears most often in three situations:

• transferring large archives between an internal disk and USB/external drives,
• moving folders to a NAS or another PC over Wi-Fi or Ethernet,
• creating backups with Windows Backup, File History, or third-party tools.

In every case, the underlying cause—and therefore the remedy—depends on where and how the data is travelling:

• locally attached media (cable, enclosure, file-system issues),
• network paths that rely on SMB/TCP (I/O buffers, driver time-outs),
• or a Windows component that interferes with both.

Note: You may see one of several message variants:

• Location is not available … The semaphore timeout period has expired.
• Error 0x80070079: The semaphore timeout period has expired.
• CMD/Log entry: ERROR_SEM_TIMEOUT (121)

All these messages point to the same error.

Quick-Solutions Cheat Sheet for Error Code 0x80070079

TABLE

Instead of randomly applying fixes, first identify the specific cause of “the semaphore timeout period has expired” error. Once the underlying issue is clear, you can confidently apply the relevant solution.

What Causes “The Semaphore Timeout Period Has Expired” Error?

The underlying trigger for this error depends entirely on where and how Windows is trying to move data—whether it’s a direct copy to a USB drive, a transfer over SMB, or an interaction with an internal component. Below are the most frequent causes.

Drive-Related Causes of Error 0x80070079

• Faulty or low-grade USB/SATA cables and ports that introduce communication errors
• Underpowered or aging external enclosures (insufficient bus power or failing bridge chipset)
• Mechanical wear or SMART-detected failures on HDDs or SSDs
• Bad sectors or file-system corruption on the source or target volume
• Outdated drive firmware or controller drivers that mishandle I/O time-outs
• FAT32 volume limits when copying single files larger than 4 GB

Network-Related Causes of Error 0x80070079

• Weak or unstable Wi-Fi signals can cause dropped SMB packets
• Speed/duplex mismatches between the network adapter and the switch/NAS port
• Outdated NIC, switch, or NAS firmware with flawed timeout handling
• Insufficient IRPStackSize buffer on the SMB server side
• TCP offload features (Large Send Offload / TCP Segmentation Offload) misprocessed by the network gear
• Network congestion or heavy parallel SMB traffic that overwhelms buffers

Windows-Related Causes of Error 0x80070079

• Real-time antivirus or third-party firewall inspections delaying I/O threads
• Corrupted or missing system files in the storage or networking stack
• Pending or failed Windows Updates that include storage-stack hot-fixes
• Incorrect registry settings affecting I/O time-out or buffer sizes
• Power-management policies (e.g., USB selective suspend) interrupting device responsiveness

How to Fix “The Semaphore Timeout Period Has Expired” Error?

To resolve Error code 0x80070079 – “the semaphore timeout period has expired,” follow the steps below that correspond to your data-transfer scenario.

Fixes for Drive-Related Data Transfers

When moving files between an internal HDD/SSD and a USB-attached or external drive, hardware faults or file-system mismatches often trigger this timeout.

1. Check the Cable & Port

Use when: copying from an internal disk to an external HDD/SSD or USB flash drive.

A poor-quality or overly long USB/SATA cable adds latency or errors, causing the transfer to stall.

Steps

1. Swap in a short (≤ 1 m), shielded USB 3.x or SATA cable.
2. Plug directly into a motherboard rear-panel port (if using a PC) or a USB 3.0 port.
3. Retry the transfer.

2. Disable USB Selective Suspend

Use when: you encounter the “semaphore timeout period expired” error involving data transfer to/from a USB drive.

Steps

1. Open Control Panel ▶ Power Options ▶ Change plan settings ▶ Change advanced power settings.

2. Expand USB settings ▶ USB selective suspend setting.

3. Set both On battery and Plugged in to Disabled, click Apply, then retry your file copy.

3. Run CHKDSK /R on Both Volumes Involved in the Data Transfer

CHKDSK locates damaged sectors and remaps them, thereby restoring timely read/write responses.

1. Type cmd in the desktop search bar and open Command Prompt.

2. Run this command: chkdsk X: /f /r
   (Replace X: with the drive letter.)
3. Press Y if prompted to reboot.
4. Reboot; then repeat for the other volume and retry your copy.

4. Convert FAT32 to NTFS

Use when: copying files larger than 4 GB to a FAT32-formatted drive.

FAT32 imposes a 4 GB file-size limit, which can cause large transfers to pause indefinitely, triggering the “semaphore timeout period expired” error.

Steps

1. Back up any data on the external drive.
2. In an elevated Command Prompt, run:
   convert X: /fs:ntfs
3. Wait for the conversion to complete and then retry the transfer.

5. Update Controller & Enclosure Firmware

Use when: you’re using a USB-to-SATA bridge in an external enclosure.

Steps

1. Identify your enclosure or adapter model (check its label or documentation).
2. Visit the vendor’s support site and download the latest USB-to-SATA bridge or chipset firmware.
3. Follow the manufacturer’s update tool instructions.
4. After updating, reconnect the drive and retry your copy.

Fixes for Network-Related Data Transfers

Transfers over SMB/TCP to a NAS or another PC can time out due to packet loss, buffer underruns, or driver issues.

1. Run the Network Adapter Troubleshooter

Windows can detect and repair common adapter misconfigurations that you may not be aware of. Relevant corrections to these can also resolve the “semaphore timeout period expired” error.

Steps

1. Go to Start ▶ Settings ▶ Update & Security ▶ Troubleshoot ▶ Additional troubleshooters.

2. Click Network Adapter ▶ Run the troubleshooter.
3. Select your adapter and follow the prompts to apply suggested fixes.
4. Reboot if instructed, then retry your file transfer.

2. Update NIC Driver & Firmware

Use when: your network card hasn’t been updated in months. This simple troubleshooting step can resolve “the semaphore timeout period expired” error in many cases.

Steps

1. Press Windows + R, type devmgmt.msc, and press Enter.
2. Expand Network adapters, right-click your NIC, and choose Update driver ▶ Search automatically.

3. If your adapter vendor offers a firmware utility (e.g., Intel, Realtek), download and run it.
4. Reboot and re-test your transfer.

3. Temporarily Disable Firewall/Antivirus

Real-time scanning can delay or block SMB packets, triggering the “semaphore timeout period has expired” error.

Steps

1. Open Control Panel ▶ Windows Defender Firewall ▶ Turn Windows Defender Firewall on or off.

2. Choose Off for both Private and Public profiles, then retry.
3. Restore your firewall settings immediately after testing.

4. Increase IRPStackSize

Use when: the SMB server is an older Windows machine or a custom file-share appliance.

A low IRPStackSize value limits concurrent I/O requests, leading to dropped packets.

Steps

1. Press Windows + R, type regedit and press Enter.

2. Navigate to HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Services\\LanmanServer\\Parameters
3. If IRPStackSize does not exist, right-click ▶ New ▶ DWORD (32-bit) Value, name it IRPStackSize.
4. Double-click IRPStackSize, select Decimal, enter 32, click OK.
5. Reboot the server/NAS.

5. Disable Large Send Offload (LSO)

Use when: your switch or router mishandles large TCP segments.

LSO offloads packet segmentation to the NIC, which can confuse older network gear.

Steps

1. In Device Manager, expand Network adapters, right-click your NIC ▶ Properties ▶ Advanced.
2. Select Large Send Offload v2 (IPv4) and (IPv6), set both to Disabled.
3. Click OK and retry the transfer.

6. Reset the Network Adapter

Use when: drivers and settings are severely corrupted.

Steps

1. Open Settings ▶ Network & Internet ▶ Status.

2. Scroll down and click Network reset, then Reset now.
3. After your PC restarts, reconnect and test the transfer.

Caution: A network reset reinstalls adapters and returns all network settings to default.

Fixes for Windows-Related Issues

When neither hardware nor network is at fault, a Windows component or system-file corruption may be to blame.

1. Repair System Files (DISM + SFC)

Why? Missing or damaged system libraries can disrupt both storage and network stacks.

Steps

1. Open an elevated Command Prompt.
2. Run:
   DISM /Online /Cleanup-image /Restorehealth
   sfc /scannow
3. Wait for each scan to finish, then reboot and retry your transfer.

Corrupted or missing system files on your PC’s drive can cause operations to time out. To resolve such an issue, you can run a System File Checker command. For detailed guidance, see our guide on running the SFC tool on Windows.

2. Apply the Latest Cumulative Windows Update

Microsoft includes hot-fixes for storage and networking time-outs in updates, which can resolve the “semaphore timeout period has expired” error.

Steps

1. Go to Settings ▶ Update & Security ▶ Windows Update.
2. Click Check for updates and install any available patches.
3. Reboot and test your file operation.

3. Perform a Clean Boot

Third-party services or startup items can interfere with I/O scheduling. A clean boot can set this right.

Steps

1. Press Windows + R, type msconfig and press Enter.

2. In System Configuration, go to the Services tab, check Hide all Microsoft services, then click Disable all.

3. On the Startup tab, click Open Task Manager, disable all startup items, then reboot.
4. Retry your transfer. To restore normal boot, re-enable services and startup items in reverse.

What If “The Semaphore Timeout Period Has Expired” Persists After Trying All Solutions?

If “the semaphore timeout period has expired” persists even after you have replaced cables, reset adapters, and repaired Windows, the fault usually lies inside the storage device itself.

On HDDs, the read/write heads may be misaligned or the motor may be seizing, preventing sectors from answering within the timeout window. On SSDs, failed NAND cells or corrupted controller firmware can lock the drive in a read-only or busy state, so every environment reports the same error.

Common hardware culprits

• HDD: head crash, damaged pre-amplifier, spindle bearing wear, PCB burn-out
• SSD: bad blocks in the FTL pool, stalled firmware update, power-loss damage
• Both: overheated controller ICs, shorted TVS diodes after a surge

At this point, repeated DIY attempts can worsen the damage. The safest path is to consult a professional data recovery service.

Don’t risk further data loss. At Stellar Data Recovery, our experts are always available to guide you, without cost or obligation. We will diagnose your storage issue and recommend the safest way forward.

We might be able to tell you how to access your data with a quick fix you might not have tried yet. If your drive or NAS equipment is beyond DIY repair and you need an expert to resolve the problem for you, we can assure you Stellar is your best chance.

Why Choose Stellar Data Recovery

1. Free expert consultation – contact our data recovery expert over the phone to understand the failure and realistic recovery odds.
2. Secure door-step collection – we arrange pick-up and transport to the nearest Stellar lab.
3. Unmatched success rates in India – ISO-certified Class 100 cleanroom, leading-edge recovery tools and tech, a donor library of 15,000+ drive parts, and technicians who specialize in head swaps, micro-soldering, and SSD controller repairs.

Reach out today—your data deserves the best care possible.

Related Hard Disk Errors You Might Encounter

If it’s not Error 0x80070079, your system might be showing one of these common hard disk issues. Here’s how to fix them:

• Facing a BIOS error that prevents your system from detecting the drive? Learn how to troubleshoot it here: Fix Hard Disk Error 3F1 Error
• Getting a startup message like “Boot Device Not Found”? This step-by-step guide can help you resolve it: Fix Boot Device Not Found Error
• Using an HP laptop and seeing a SMART error warning? Understand what it means and what to do next: Fix SMART Hard Disk Error Code 301 in HP Laptop
• Struggling with a file transfer or drive access issue? Here’s how to deal with it: Fix External Hard Disk I/O Device Error

FAQs

1. What is the semaphore time period in Windows?

It is the built-in time-out Windows gives a storage or network device to acknowledge a read/write request. If the device stays silent beyond that interval, the semaphore timeout period has expired error is raised.

2. What does “timeout period expired” mean during file copy?

It signals that the OS stopped waiting for a reply from the drive or remote host. Causes include bad USB cables, Wi-Fi drops, or driver bugs; the copy halts with error 0x80070079.

3. Why does the semaphore timeout period has expired appear in SQL Server?

During a backup or query, SQL writes large blocks via SMB. Packet loss or small IRPStackSize values make the network stack exceed its wait window, returning the same semaphore-timeout failure code to SQL.

4. Is 0x80070079 the same as “the semaphore timeout has expired” on Windows 10 or 7?

Yes. Both Windows 7 and Windows 10 map error 0x80070079 to the string “the semaphore timeout period has expired”; only the wording in pop-ups differs slightly.

5. None of the fixes work—what next?

If every cable, port, and driver check fails, the drive’s heads, NAND, or controller firmware may be physically damaged. Professional data recovery services like Stellar can image the device in a dust-free environment before failure becomes permanent.