flowable/flowable-engine · error · FlowableObjectNotFoundException

Could not find a process instance with id '" +…

Error message

Could not find a process instance with id '" + processInstanceId + "'.

What it means

getProcessInstanceFromRequestWithoutAccessCheck queries runtimeService.createProcessInstanceQuery().processInstanceId(id).singleResult() and throws FlowableObjectNotFoundException when no running process instance matches the given id. Note it only sees running instances, not completed/historic ones.

Solutions

1. Verify the processInstanceId exists via /runtime/process-instances list query
2. If the instance may have completed, query /history/historic-process-instances/{id} instead
3. Check that you are using the process instance id (e.g. '5001') and not the business key or definition id

Example fix

// before
GET /runtime/process-instances/5001   // instance already completed -> 404
// after
GET /history/historic-process-instances/5001

const list = await api.get('/runtime/process-instances?processInstanceId=' + id); if (!list.data || list.data.length === 0) { /* fall back to history endpoint */ }

function isNotFound(e) { return e && (e.status === 404 || e.message.includes('Could not find a process instance')); }

try { return await api.get('/runtime/process-instances/' + id); } catch (e) { if (e.status === 404) return await api.get('/history/historic-process-instances/' + id); throw e; }

When it happens

Trigger: GET /runtime/process-instances/{processInstanceId} with an id that does not exist, was mistyped, or refers to a process instance that has already ended (only history retains those).

Common situations: Client cached an id of an instance that finished between calls; confusion between process instance id and business key or process definition id; querying a historic instance through the runtime endpoint instead of /history/historic-process-instances.

Understand the failure class

Background: "Not found" and "does not exist" errors: why "Task not found", "No such folder", and "Can't find" fire when a lookup comes back empty — this error's family across 14 libraries.

Related errors

• Batch part with id ' ' does not have a batch part document.
• Batch with id ' ' does not have a batch document.
• Cannot find process definition with id
• Cannot find process instance with id
• Cannot find process instance with id

AI-assisted analysis of flowable/flowable-engine@d6d39ce1c6 (2026-09-11). Data as JSON: /api/errors/fbc16a5b4bdbbd68. Report an issue: GitHub.

Appendix: source

Thrown at modules/flowable-rest/src/main/java/org/flowable/rest/service/api/runtime/process/BaseProcessInstanceResource.java:395

     */
    protected ProcessInstance getProcessInstanceFromRequest(String processInstanceId) {
        ProcessInstance processInstance = getProcessInstanceFromRequestWithoutAccessCheck(processInstanceId);

        if (restApiInterceptor != null) {
            restApiInterceptor.accessProcessInstanceInfoById(processInstance);
        }

        return processInstance;
    }

    /**
     * Returns the {@link ProcessInstance} that is requested without calling the access interceptor
     * Throws the right exceptions when bad request was made or instance was not found.
     */
    protected ProcessInstance getProcessInstanceFromRequestWithoutAccessCheck(String processInstanceId) {
        ProcessInstance processInstance = runtimeService.createProcessInstanceQuery().processInstanceId(processInstanceId).singleResult();
        if (processInstance == null) {
            throw new FlowableObjectNotFoundException("Could not find a process instance with id '" + processInstanceId + "'.");
        }
        return processInstance;
    }
}

View on GitHub (pinned to d6d39ce1c6)