User Control - View Lock Table – GGP Systems Help Center

📝 Overview

GGP automatically places locks on files currently in use to prevent multiple users from editing the same data simultaneously. You can view these locks via Tools | View Lock Table in User Control Maintenance, which opens the LOCKTABLE.DAT file.

🔒 Types of Locks

Lock Type	Description
Overlay Lock	When working on an overlay (e.g., importing data in Setup Application). Shows `RecordNumber` as `OverlayLock` and displays the overlay number in `OverlayNumber`.
Overlay List Lock	Occurs when an overlay is selected/highlighted in the overlay list (Home, Group, Dept, Corp). The `OverlayNumber` shows which overlay table is in use.
Record Lock	When a file is in use, such as viewing or editing a record. If viewing, lock type is `Read`. If editing, lock type changes to `Write` to prevent concurrent edits. `OverlayNumber` shows the overlay being used and `RecordNumber` shows the record ID locked.

🔄 Lock Table Behavior

The Lock Table auto-refreshes while GGP is open.
It activates as soon as the first user opens GGP and stays active until all users exit all GGP applications.
The table size remains controlled by reusing available lock records (signified by User ID = 0), or creating new ones if none are free.

🔐 Lock Management in GGP v3.0+

GGP enforces exclusivity for Setup Application tables and shows the LoginID of any user already locking a table if another user tries to access it.
Lock records are maintained within the system Lock folder by the OverlayTableList.

🛠️ Manual Unlocking

If locks are not cleared automatically (e.g., after a crash), you can manually edit the OverlayTableList.ini file.
Clicking the Locks button opens OverlayTableList.ini in Notepad, showing the lock paths on overlay tables (Home, Group, Dept, Corp).
To unlock, change the path to include Unlocked instead of the username.

🚨 Unlock Button Warning

Use the Unlock button cautiously:

Only unlock records if the system crashed and left locks behind.
Do NOT unlock if a record is actively being edited by a user—doing so can cause errors and corrupt the current editing session and subsequent locks.