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Error Code 21

SteelSeries Error Code 21: GG Sonar audio startup error

Verified with sources2 sourcesReviewed Oct 19, 2026
Technician coming? See the 2 steps they must show you
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D-KuruCC BY-SA 3.0 atImage source

Risk level

Low

Usually safe to check without specialist tools.

Urgency

Medium

Quick answer

Error Code 21 in SteelSeries GG Sonar means Microsoft Visual C++ 2015-2022 Redistributable (x64) is outdated or corrupted. Repair that package in Windows Settings > Apps > Installed Apps or install the latest x64 version from Microsoft's official site.

Safety first

Stop and check this first

  • Use only Microsoft's official page for the 2015-2022 Redistributable (x64) and SteelSeries.com for GG; when refreshing GG to repair Sonar files, install over the existing installation so your custom Sonar presets are retained.

Safe checks you can perform

  • Confirm Error Code 21 and repair the x64 redistributable in Windows
  • Install the latest official 2015-2022 Redistributable (x64) from Microsoft
  • Reinstall SteelSeries GG over the existing setup if update files are missing

Leave these tasks to a qualified professional

  • Do not attempt this professional task: Repair or update the official Microsoft Visual C++ 2015-2022 (x64) package
  • Do not attempt this professional task: Restore SteelSeries GG files in place while preserving Sonar presets

What a technician must be able to justify

Technician visit

These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.

These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.

  1. Repair or update the official Microsoft Visual C++ 2015-2022 (x64) package

    What they doThe technician checks Windows Settings > Apps > Installed Apps for Microsoft Visual C++ 2015-2022 Redistributable (x64), runs Modify > Repair, or installs the latest x64 package from Microsoft's official page.

    They must show youthe repaired or updated Microsoft Visual C++ 2015-2022 Redistributable (x64) entry and Sonar launching afterward.

    In writingwhether the x64 redistributable was repaired or reinstalled, Windows update status, and whether Error Code 21 cleared.

  2. Restore SteelSeries GG files in place while preserving Sonar presets

    What they doIf update-related Sonar errors (codes 15 through 19) accompany the fault, the professional downloads the latest GG installer from SteelSeries.com and installs it over the existing installation to repair missing files without erasing custom presets.

    They must show youthe latest SteelSeries GG version installed over the current setup and intact custom Sonar presets.

    In writingrecorded Sonar error code, official GG version installed in place, and final startup verification.

Before accepting a part or repair

Nothing has been shown yet. Do not accept a part swap based on the code alone.

Follow these steps

Note: Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.

  1. Confirm Error Code 21 and repair the x64 redistributable in Windows

    No special tools

    Who:
    you, on the Windows PC where SteelSeries GG Sonar displays Error Code 21.
    How:
    open Windows Settings > Apps > Installed Apps, type redistributable in the search bar, find Microsoft Visual C++ 2015-2022 Redistributable (x64), click the three dots next to it, select Modify, and choose Repair.
    Result that matters:
    run the built-in repair for the exact x64 redistributable specified in the Error Code 21 guide.
    If the repair completes and Sonar starts without Error Code 21:
    keep a record of the repair.
    If repair is unavailable or Error Code 21 returns:
    install the latest official Microsoft package next.
    Evidence to keep:
    Microsoft Visual C++ 2015-2022 Redistributable (x64) entry in Installed Apps and the Repair outcome.

    Evidence: Sonar Error code 21 and what to do!

  2. Install the latest official 2015-2022 Redistributable (x64) from Microsoft

    No special tools

    Who:
    you, downloading directly from the official Microsoft Learn page cited by SteelSeries.
    How:
    visit Microsoft's official Visual C++ Redistributable download page, download the latest 2015-2022 Redistributable (x64) installer, run it to completion, and check that Windows updates are current.
    Result that matters:
    replace an outdated or broken x64 redistributable with the current official version required by Sonar.
    If Sonar launches normally after installing the updated x64 package:
    record that Visual C++ 2015-2022 (x64) build.
    If the startup issue remains or shifts to an update error such as codes 15-19:
    refresh the GG installation.
    Evidence to keep:
    completed official 2015-2022 (x64) installer run and Sonar's startup status afterward.

    Evidence: Sonar Error code 21 and what to do!

  3. Reinstall SteelSeries GG over the existing setup if update files are missing

    No special tools

    Who:
    you, using the official SteelSeries GG installer from SteelSeries.com.
    How:
    if Sonar also exhibits update corruption such as Error Codes 15 through 19, download the latest GG version from SteelSeries.com and install it directly over your existing installation so custom Sonar presets and settings are retained.
    Result that matters:
    update missing or corrupted GG files without performing a full uninstall that would remove presets.
    If Sonar opens with your custom presets preserved:
    record the GG version installed.
    If Error Code 21 persists after repairing Visual C++ and updating GG:
    share these results with a technician or support.
    Evidence to keep:
    installed SteelSeries GG version and a screenshot of any remaining Sonar error screen.

    Evidence: Sonar Error code 21 and what to do! · Sonar Error code 15, 16, 17, 18 and 19 and what they mean!

Still not solved

If the error persists, stop here. See what the technician must do and show you.

Where this code applies

A code is meaningful only inside the right product and version context.

Primary scope

System
Gaming and consoles
Brand
SteelSeries
Product type
PC peripherals and accessories

Known code variants

  • Código de error 21 en Sonar
  • Error 21 SteelSeries GG Sonar
  • Sonar Error Code 21
  • SteelSeries GG Error Code 21

What it means

SteelSeries' official article 'Sonar Error code 21 and what to do!' states that Sonar requires Microsoft's Visual C++ 2015-2022 Redistributable (x64) to work properly and will fail to start with Error Code 21 if that package is broken or outdated. Unlike Sonar Error Codes 15 through 19, which SteelSeries attributes to missing or corrupted GG files after an update, Error Code 21 specifically targets the x64 Visual C++ redistributable. Behavior across other software modules or devices may differ, and this error code alone never proves that your audio hardware is defective.

Warnings and stop conditions

  • Lowsource verified

    Use only Microsoft's official page for the 2015-2022 Redistributable (x64) and SteelSeries.com for GG; when refreshing GG to repair Sonar files, install over the existing installation so your custom Sonar presets are retained.

    Evidence: Sonar Error code 21 and what to do! · Sonar Error code 15, 16, 17, 18 and 19 and what they mean!

Symptoms and causes

Probable causes · in order

  • Corrupted Microsoft Visual C++ 2015-2022 Redistributable (x64)Common

    When the installed Microsoft Visual C++ 2015-2022 Redistributable (x64) package is broken or corrupted in Windows, Sonar cannot launch and reports Error Code 21.

    Evidence: Sonar Error code 21 and what to do!

  • Outdated Visual C++ 2015-2022 (x64) package or Windows buildPossible

    SteelSeries explains that an outdated 2015-2022 Redistributable (x64) prevents Sonar from starting and advises keeping Windows and the redistributable updated.

    Evidence: Sonar Error code 21 and what to do!

  • Missing or corrupted GG update files when accompanied by codes 15-19Less common

    If Sonar also reports Error Codes 15, 16, 17, 18, or 19 after an update, SteelSeries links those codes to missing files or data corruption in the SteelSeries GG installation.

    Evidence: Sonar Error code 15, 16, 17, 18 and 19 and what they mean!

Virtual technician

Does Error Code 21 still appear after these checks?

Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.

Start diagnosis

Sources and technical references

  1. 1

    Sonar Error code 21 and what to do!

    SteelSeries · 2026 · official_doc

  2. 2

    Sonar Error code 15, 16, 17, 18 and 19 and what they mean!

    SteelSeries · 2026 · official_doc

Sources: Sonar Error code 21 and what to do! · Sonar Error code 15, 16, 17, 18 and 19 and what they mean!reviewed 2026-10-19 · verified

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