| Previous | Next |
| hrNotInTransaction | hrInvalidCountry |
hrTooManyActiveUsers
Why this is more specific than the message text
hrTooManyActiveUsers means the engine reached its active-user or concurrent-session workload limit.
This is the legacy Directory Service backup/restore HRESULT form of JET_errTooManyActiveUsers (0xC8000423).
The key comparison is: hrOutOfSessions is allocation exhaustion; this code emphasizes active database users. The first useful observation is to count active sessions, long transactions, blocked requests, and connection-pool ownership. This evidence identifies the exhausted pool so a leak, long transaction, concurrency spike, and hard capacity limit are not confused.
Related ESE conditions
hrOutOfSessions | the instance cannot allocate another JET_SESID |
|---|---|
hrTooManyAttachedDatabases | the instance reached its attached-database limit |
hrOutOfMemory | ESE or its caller could not reserve memory required for the operation |
The ESE objects in play
| Diagnostic layer | bounded engine, process, and storage resources |
|---|---|
| Typical API surface | instance system parameters, sessions, cursors, temporary tables, database attachment, and file growth |
| Code-specific condition | the engine reached its active-user or concurrent-session workload limit |
| First corrective direction | shed or queue work, end abandoned sessions, and shorten transactions before raising limits |
Long transactions can retain versions and indirectly amplify memory and log pressure. A retry without closing owners or adding capacity often repeats the same failure and increases load.
Data for a reproducible case
- Code-specific observation: count active sessions, long transactions, blocked requests, and connection-pool ownership.
- relevant JET_param values and process or system capacity at first failure; associate it with this result rather than with a later generic exception.
- the oldest transaction, longest-held cursor, or file growth operation retaining the resource.
- live resource counts grouped by session and request owner.
Corrective workflow
- Freeze the failing request context and record
0xC8000423, the Jet API name, and the current instance/session ownership. - Verify the code-specific precondition: count active sessions, long transactions, blocked requests, and connection-pool ownership.
- Apply the targeted fix: shed or queue work, end abandoned sessions, and shorten transactions before raising limits.
- Before retrying the operation, reconcile resource counts, owner cleanup, and capacity after the correction.
Actions that can hide or worsen the problem
- Do not raise limits before checking ownership and release paths.
- Do not create a retry storm while the exhausted resource remains unavailable.
Technical references
- JET_param enumeration.
- Transactions and save points
- ESE files and storage paths
- ESE source repository
- Microsoft: JET_ERR enumeration
Looking for a different code? Search another status or error code.