Troubleshooting Error Code 300:9 and Sybase Engine Startup Failures in SIMATIC PCS 7

In SIMATIC PCS 7 and STEP 7, Error Code 300:9 ('The database cannot be started or accessed') indicates that the Sybase SQL Anywhere database engine failed to initialize the project database (amdbase.db) because the communication port (default TCP 2638) is blocked or occupied by a hung database process, or because the database file is write-protected or corrupt. To resolve Error 300:9, terminate all background instances of dbeng*.exe in Task Manager, verify that port 2638 is not blocked by third-party firewalls, ensure the project directory is not marked read-only, and run the project reorganization utility in SIMATIC Manager.

Executive Summary

During routine project opening or archive retrieval in SIMATIC PCS 7 V9.0 SP3, engineers may encounter an abrupt modal error stating Error code 300:9 - Database error. This error halts SIMATIC Manager from opening the selected S7 program, preventing access to CFC charts, hardware configurations, and block folders. Unlike general Windows file-sharing errors, Error 300:9 is a specific diagnostic code generated by the STEP 7 database abstraction layer when the underlying Sybase database engine cannot spawn or connect to the local socket interface. This article explains the technical origin of Error 300:9, outlines the port allocation and file access mechanics, and provides an authoritative recovery procedure.

Architecture and Fundamental Mechanics

Error Code 300:9 Origin, TCP Socket Binding, and Sybase Initialization Mechanics:

Anatomy of Error Code 300:9:
Within the Siemens S7 database architecture, errors prefixed with 300: originate from the Database Server Management Layer (s7tgtopx.exe interacting with dbeng*.exe).
Subcode :9 specifically signifies: Database Initialization Failure / Socket Bind Failure.
When SIMATIC Manager attempts to open an S7 project, it issues a command to launch the Sybase database engine with parameters pointing to <ProjectPath>\AMOBIJS\amdbase.db.
Root Cause 1: Port Collision on TCP Port 2638:
Sybase SQL Anywhere listens on standard port TCP 2638 for inter-process communication between SIMATIC Manager and the database server.
If an ungracefully terminated session leaves a hidden dbeng16.exe process bound to port 2638, the new engine instance fails to bind the socket and crashes, returning Error 300:9.
Root Cause 2: File System Attribute Restrictions:
If an archive was extracted from an optical disc, ISO image, or backup directory that preserved Read-Only file attributes, amdbase.db cannot create its temporary transaction handles, causing immediate startup rejection.
Root Cause 3: Incomplete Database Detachment:
If a user abruptly disconnected a network drive or killed SIMATIC Manager while a chart compilation was active, the database header may flag that the database is still attached to an active process.

Step-by-Step Implementation Procedure

Terminate All Lingering Database Processes:
* Close all Siemens applications.
* Open Windows Command Prompt as Administrator and execute:
cmd taskkill /F /IM dbeng16.exe /T taskkill /F /IM s7tgtopx.exe /T taskkill /F /IM s7cfcapp.exe /T
* Verify that the commands return successful termination confirmation.
Verify TCP Port 2638 Availability:
* In Command Prompt, execute:
cmd netstat -ano | findstr 2638
* If any process is listening on port 2638, identify its PID from the rightmost column and terminate it via taskkill /F /PID <PID>.
Clear Read-Only Attributes on the Project Directory:
* In Windows File Explorer, browse to the project folder.
* Right-click the project root folder and select Properties.
* Clear the Read-only checkbox.
* Click Apply; in the confirmation dialog, select Apply changes to this folder, subfolders and files and click OK.
Execute Project Reorganization in SIMATIC Manager:
* Open SIMATIC Manager.
* Select menu File > Reorganize....
* In the dialog, browse to the project folder, select the .s7p file, and click OK.
* The reorganization utility rebuilds database indices, cleans orphan references, and compacts amdbase.db.
Re-open the Project:
* Select File > Open and open the reorganized project.
* Verify that charts and blocks load cleanly without Error 300:9.

Verification

Launch SIMATIC Manager; open the affected project.
Confirm that the project navigation tree renders with full component hierarchies and no modal 300:9 dialogues.
Open CFC, edit a test chart, and perform a successful 'Save and Compile' check.

Limitations and Operational Precautions

If Error 300:9 persists after terminating hung processes and clearing read-only attributes, amdbase.db may have suffered severe physical disk block corruption. In this case, restore the project from the most recent verified backup archive.