WinTrouble

How to fix ERROR_SEM_TIMEOUT

Code:121 (0x79)
Teracopy: Reports error

Description

The semaphore timeout period has expired

Causes

The Win32 error code ERROR_SEM_TIMEOUT with the numerical value 121 indicates that a semaphore timeout period has expired. This error commonly arises when a system process or application fails to communicate with a device or network resource within a specified time frame. Recognizing the underlying causes and applying appropriate solutions can help resolve this error effectively.

What is a Semaphore Timeout?

In computing, a semaphore is a synchronization mechanism used to control access to shared resources. A semaphore timeout occurs when a process waits longer than the allowed time for a resource to become available. This can happen due to delays in communication, unresponsive devices, or network issues.

Common Causes

  1. Network Connectivity Issues:

    • Unstable or slow network connections.
    • Intermittent network outages or high latency.
    • Incorrect network configurations.

  2. Hardware Problems:

    • Faulty or failing hard drives, especially external or network-attached storage.
    • Defective cables (USB, SATA, network) causing communication delays.
    • Malfunctioning network adapters or routers.

  3. Driver and Firmware Issues:

    • Outdated or corrupted device drivers.
    • Incompatible or outdated firmware on devices.

  4. Resource Contention:

    • Multiple applications competing for the same resource.
    • Deadlocks caused by improper synchronization in applications.

  5. High System Load:

    • Insufficient system resources (CPU, memory) leading to slow response times.
    • Overloaded servers or network devices.

  6. Software Conflicts:

    • Conflicts between applications accessing the same device or resource.
    • Bugs or errors within applications causing delays.

  7. Incorrect Timeout Settings:

    • Timeout periods set too short for the operation to complete.
    • Misconfigured system or application settings.

  8. Network Adapter and Switch Configuration Issues:

    • Mismatched duplex levels or transfer speed settings between network adapters and switch ports.
    • Autosense settings not correctly detecting network adapter speeds.
    • Incompatibility between network adapters and motherboards or other hardware components.

Solutions

1. Check Network Connections

  • Verify Physical Connections:

    • Ensure all network cables are securely connected.
    • Replace damaged or worn-out cables.
    • Swap Cables: Try using a different network cable between the failing system and the hub or switch to rule out cable issues.

  • Test Network Stability:

    • Use the ping command to check latency and packet loss.
      • Open Command Prompt and type ping google.com -t to test internet connectivity.
    • If issues are detected, restart network devices like routers and switches.

  • Reset Network Adapters:

    • Open Command Prompt as an administrator and run:
      • netsh winsock reset
      • netsh int ip reset
    • Restart your computer after executing the commands.

2. Check and Adjust Network Adapter and Switch Settings

  • Match Duplex and Speed Settings:

    • Ensure that both the network adapter and the switch port are set to the same duplex mode (full or half) and speed (10 Mbps, 100 Mbps, or 1 Gbps).
      • Network Adapter Settings:
        • Go to Device Manager > Network Adapters > Right-click your adapter > Properties > Advanced tab.
        • Adjust the Speed & Duplex setting to match the switch port.
      • Switch Port Settings:
        • Access the switch's management interface to verify and adjust port settings.

  • Disable Autosensing if Necessary:

    • Autosensing may not correctly detect the speed of some network adapters.
    • Manually set the network adapter and switch port to the desired speed and duplex settings.

  • Test with Lower Settings:

    • Temporarily set the network adapter to half-duplex and 10 Mbps to see if the connection stabilizes.
    • If successful, incrementally increase the speed settings while testing for connectivity loss.

  • Common Scenarios:

    • Moved Computer: If a computer was moved to a new Ethernet switch port that auto-negotiates speed, but the adapter is forced to a static speed and duplex, mismatches can occur.
    • Forced Settings: Both the switch port and network adapter are forced to high speeds (e.g., 1 Gbps full-duplex), but hardware limitations prevent proper communication.

3. Update or Reinstall Device Drivers

  • Device Manager:

    • Press Win + X and select Device Manager.
    • Locate network adapters or other relevant devices.
    • Right-click and select Update driver.
    • Choose Search automatically for updated driver software.

  • Manufacturer's Website:

    • Download the latest drivers from the device manufacturer's official website.
    • Install the drivers following provided instructions.

4. Replace Faulty Hardware

  • Network Adapters:

    • If the network adapter is suspected to be incompatible or faulty, replace it with a proven reliable model.

  • Cables and Connections:

    • Replace defective cables (Ethernet, USB, SATA) to eliminate communication delays caused by hardware faults.

  • Hardware Compatibility:

    • Ensure that the network adapter is compatible with the motherboard and other system components.

5. Reduce System Load and Close Conflicting Applications

  • Resource Monitor:

    • Press Ctrl + Shift + Esc to open Task Manager.
    • Go to the Processes or Performance tab to monitor resource usage.
    • Identify and close applications consuming excessive resources.

  • Clean Boot:

    • Perform a clean boot to start Windows with minimal drivers and startup programs.
      • Press Win + R, type msconfig, and press Enter.
      • Under the Services tab, check Hide all Microsoft services and click Disable all.
      • Go to the Startup tab and click Open Task Manager. Disable all startup items.
      • Restart your computer.

6. Adjust Timeout Settings

  • Increase Timeout Values:

    • For specific applications, adjust the timeout settings if possible.
    • In network configurations, increase timeout values to accommodate delays.

  • Registry Tweaks (Advanced Users):

    • Warning: Modifying the registry can cause system instability. Proceed with caution.
    • Open Registry Editor (regedit).
    • Navigate to appropriate keys for the device or service experiencing timeouts.
    • Modify timeout values as recommended by documentation or support.

7. Update Firmware and Software

  • Device Firmware:

    • Check for firmware updates for network adapters, routers, and switches.
    • Follow the manufacturer's instructions carefully when updating firmware.

  • Operating System Updates:

    • Go to Settings > Update & Security > Windows Update.
    • Click Check for updates and install any available updates.

8. Scan for Malware

  • Full System Scan:

    • Use reputable antivirus software to perform a comprehensive scan.
    • Remove or quarantine any detected threats.

  • Anti-Malware Tools:

    • Utilize tools like Malwarebytes to detect and remove malware that may cause system slowdowns.

9. Reinstall or Repair Applications

  • Repair Installation:

    • For applications experiencing issues, use the repair option if available.
      • Go to Control Panel > Programs and Features.
      • Select the application and choose Repair.

  • Reinstall Applications:

    • Uninstall and reinstall the application to ensure all components are properly installed.