user service ' ': environment value for contains , which…

Error message

user service '{}': environment value for {key} contains {c:?}, which cmd.exe would reinterpret; set it inside the program instead

What it means

Environment VALUES for a user service are injected through `set "key=value"` inside cmd.exe. Characters cmd.exe reinterprets (quotes, percent expansion, chain operators, redirection, escapes, newlines) would change what actually gets set, so exec_action rejects any value containing them.

Solutions

Remove or escape the offending character from the value
Set the variable inside the program itself (read from a protected file) instead of via the environment map
Point the value at a path/config without special characters

Example fix

// before
environment: { "TOKEN": "a%b&c" }
// after
environment: { "TOKEN_FILE": "C:\\secrets\\token.txt" }

Defensive patterns

Strategy: validation

Validate before calling

const bad = Object.entries(svc.environment).find(([, v]) => /["%&|<>^\r\n]/.test(v));
if (bad) throw new Error(`env value for ${bad[0]} contains cmd.exe metacharacter`);

Type guard

function isCmdSafeValue(v) { return typeof v === 'string' && ![...v].some(c => '"%&|<>^\r\n'.includes(c)); }

Try / catch

try { renderServiceXml(svc); } catch (e) { if (String(e).includes('cmd.exe would reinterpret')) { moveSecretsToFile(svc.environment); } else throw e; }

Prevention

Keep secrets and tokens with special characters in files read by the program, not env values
Strip CRLF when loading env values from Windows text files
Review env values for % (expansion) and & | < > ^ (operators) before saving

When it happens

Trigger: render_xml -> exec_action on Windows with request.environment containing a value that includes '"', '%', '&', '|', '<', '>', '^', '\n', or '\r'.

Common situations: Passwords or tokens containing '%' or '&' in env values; shell snippets pasted into env values; values with trailing CRLF read from a Windows text file.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

AI-assisted analysis of jdx/mise@533346cc37 (2026-09-17). Data as JSON: /api/errors/3aaa7d81d7442147. Report an issue: GitHub.

Appendix: source

Thrown at src/system/scheduled_tasks.rs:220

/// change are rejected rather than passed through differently.
fn exec_action(request: &ScheduledTaskRequest) -> Result<(String, String)> {
    let (program, args) = split_command(&request.command);
    if request.environment.is_empty() {
        return Ok((program, args));
    }
    let mut sets = vec![];
    for (key, value) in &request.environment {
        if key.is_empty() || key.contains(['=', '"', '%', '\n', '\r']) {
            bail!(
                "user service '{}': environment key {key:?} cannot be set through cmd.exe",
                request.name
            );
        }
        if let Some(c) = value
            .chars()
            .find(|c| matches!(c, '"' | '%' | '&' | '|' | '<' | '>' | '^' | '\n' | '\r'))
        {
            bail!(
                "user service '{}': environment value for {key} contains {c:?}, which cmd.exe would reinterpret; set it inside the program instead",
                request.name
            );
        }
        sets.push(format!("set \"{key}={value}\""));
    }
    // the command line goes through cmd.exe too: what it would split or
    // chain is rejected the same way, rather than run differently
    if let Some(c) = format!("{program} {args}")
        .chars()
        .find(|c| matches!(c, '%' | '&' | '|' | '<' | '>' | '^' | '\n' | '\r'))
    {
        bail!(
            "user service '{}': the command contains {c:?}, which cmd.exe would reinterpret when `environment` is set; move it into a script",
            request.name
        );
    }
    let program = if program.contains(char::is_whitespace) {

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