git-ecosystem/git-credential-manager · error · Trace2Exception

Failed to set Git configuration entry

Error message

Failed to set Git configuration entry '{name}'

What it means

Thrown by GitConfiguration.Set when `git config <name> <value>` exits non-zero. The trace line includes the exit code and level. Common causes are an invalid section/key name or a locked/unwritable config file.

Solutions

1. Verify the key uses valid 'section.subsection.key' format (run `git config --get <name>` first)
2. Check the target config file is writable (permissions, read-only attribute, file lock)
3. Run the equivalent `git config <level> <name> <value>` manually to see git's error
4. Confirm the repository/level location exists before writing

Example fix

// before
config.Set(GitConfigurationLevel.Local, "httpSslVerify", "false"); // throws: invalid key
// after
config.Set(GitConfigurationLevel.Local, "http.sslVerify", "false"); // valid section.key

static bool IsValidConfigKey(string name) {
    var parts = name.Split('.');
    return parts.Length >= 2 && parts.All(p => p.Length > 0);
}
// call only if IsValidConfigKey(name)

try { cfg.Set(level, name, value); }
catch (GitException ex) { log.Error($"Set '{name}' failed: {ex.Message}"); }

When it happens

Trigger: Calling Set(level, name, value) where the key name is malformed (e.g. missing section orsubsection dot), the target config file is read-only, or git rejects the write (invalid key, unwritable location).

Common situations: Passing 'httpSslVerify' without a section instead of 'http.sslVerify'; writing to a repo whose .git/config is read-only or owned by another user; trying to set in a level whose file cannot be created.

Understand the failure class

Background: "git command failed": what it means when a tool shells out to git and git exits non-zero — this error's family across 21 libraries.

Related errors

• Failed to add Git configuration entry
• Failed to unset Git configuration entry
• Failed to replace all Git configuration multi-valued entries
• Failed to unset all Git configuration multi-valued entries
• Failed to enumerate all Git configuration entries

AI-assisted analysis of git-ecosystem/git-credential-manager@e8ce762cd0 (2026-09-11). Data as JSON: /api/errors/314ff783c1e15e18. Report an issue: GitHub.

Appendix: source

Thrown at src/Core/GitConfiguration.cs:598

        public void Set(GitConfigurationLevel level, string name, string value)
        {
            EnsureSpecificLevel(level);

            string levelArg = GetLevelFilterArg(level);
            using (ChildProcess git = _git.CreateProcess($"config {levelArg} {QuoteCmdArg(name)} {QuoteCmdArg(value)}"))
            {
                git.Start(Trace2ProcessClass.Git);
                git.WaitForExit();

                switch (git.ExitCode)
                {
                    case 0: // OK
                        InvalidateCache();
                        break;
                    default:
                        _trace.WriteLine($"Failed to set config entry '{name}' to value '{value}' (exit={git.ExitCode}, level={level})");
                        throw GitProcess.CreateGitException(git, $"Failed to set Git configuration entry '{name}'");
                }
            }
        }

        public void Add(GitConfigurationLevel level, string name, string value)
        {
            EnsureSpecificLevel(level);

            string levelArg = GetLevelFilterArg(level);
            using (ChildProcess git = _git.CreateProcess($"config {levelArg} --add {QuoteCmdArg(name)} {QuoteCmdArg(value)}"))
            {
                git.Start(Trace2ProcessClass.Git);
                git.WaitForExit();

                switch (git.ExitCode)
                {
                    case 0: // OK
                        InvalidateCache();

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