Resolving OS Download Failure 'Error Changing Computer Name to Station-Name'

The error 'Beim Ändern des Computernamens im Projekt in ist ein Fehler aufgetreten!' (An error occurred while changing the computer name in the project to ) during a PCS 7 OS project download occurs when the Engineering Station cannot update the target computer name in the WinCC project database. The primary root causes are absent or misconfigured Reverse Lookup Zones (missing PTR records) in domain DNS, mismatched NetBIOS station names between SIMATIC Manager and the target PC, or active background WinCC processes (such as CCProjectMgr.exe) locking project files on the destination station. Resolving DNS reverse resolution, ensuring identical station naming in WinCC Computer Properties, and deactivating all WinCC runtime services on the target PC resolves the download failure.

OS Project Download and Remote Renaming Architecture

When an automation engineer downloads an Operator Station project from the SIMATIC Manager Engineering Station to a target OS (Single Station, OS Server, or Standby Server), STEP 7 executes a structured multi-stage file transfer over the Terminal Bus. The ES first creates a localized copy of the WinCC project database files (<ProjectName>.mcp, .mdf, .ldf), transfers them across network file shares, and invokes remote Distributed COM (DCOM) routines.

As the final step of the transfer, the Engineering Station invokes an automated script inside the target station's WinCC environment to update the project's internal Computer Name property from the ES computer name to the target OS station name. If the network cannot bidirectional-resolve hostnames, or if the destination database is locked by background services, this automated rename script throws the error.

Root Causes: DNS Reverse Lookup, NetBIOS, and File Locks

Engineering analysis of the download protocol reveals three primary failure points:

Missing DNS Reverse Lookup (PTR Record): In Windows Active Directory domains or managed subnets, DCOM and RPC security verification performs forward and reverse DNS lookups. If the DNS server lacks a Reverse Lookup Zone or if the PTR record for the target OS station IP is missing, the security handshake times out during the remote rename invocation.
Station Name Mismatch in Project Properties: If the Computer Name configured under the WinCC Explorer properties on the ES differs from the physical Windows hostname of the target machine, the database update routine fails validation.
Locked Project Files on Target Station: If WinCC Runtime was improperly closed, background processes such as CCProjectMgr.exe, CCWinCCDataServer.exe, or SQL Server lock the .mcp or .dcf files, preventing the rename script from modifying database records.

Target System Communication and Name Resolution Matrix

The following table identifies key network and software requirements for successful OS project downloads:

Diagnostic LayerRequirementVerification Command / CheckConsequence if MisconfiguredForward DNSHostname resolves to target IPping <STATION-NAME>Target PC cannot be contactedReverse DNSTarget IP resolves to exact Hostnamenslookup <Target_IP>Remote name change fails with security timeoutNetBIOS / hostsIdentical names in lmhosts / hostsCheck C:\Windows\System32\drivers\etc\DCOM authentication delaysWinCC File LocksZero active WinCC background tasksTask Manager -> End CCProjectMgr.exeProject database cannot be modifiedNetwork ShareShared folder has Full ControlProperties -> Sharing -> SIMATIC HMI groupAccess Denied error during transfer

Step-by-Step Troubleshooting and Resolution Procedure

To resolve the computer name change failure during OS download:

Configure DNS Reverse Lookup Zone and PTR Record:
- On the plant Domain Controller / DNS server, open DNS Manager.
- Verify that a Reverse Lookup Zone exists for the Terminal Bus subnet (e.g., 192.168.1.x).
- Ensure a valid Pointer (PTR) record maps the target OS IP address to its exact hostname (<STATION-NAME>).
- On the ES, open Command Prompt and test: nslookup <Target_IP>. The output must return <STATION-NAME>.
Verify WinCC Computer Name Settings on ES:
- On the ES, open the OS project directly in WinCC Explorer.
- In the navigation tree, click Computer.
- Double-click the computer icon in the right pane to open Computer Properties.
- Ensure the configured computer name matches the physical hostname of the destination PC exactly.
- Close WinCC Explorer on the ES.
Clear Locked WinCC Processes on Target OS PC:
- On the destination PC station, completely close WinCC.
- Run the Siemens utility Reset_WinCC.vbs (located in <Drive>:\Program Files (x86)\Siemens\WinCC\bin\Reset_WinCC.vbs).
- Open Task Manager and verify that all CC*.exe processes have terminated.
Re-Execute OS Project Download:
- In SIMATIC Manager on the ES, right-click the OS object and select PLC -> Download.
- Select Scope: Entire OS (if previous downloads were aborted) and click OK.
- The download will complete without error, and the project will open with the correct computer name.

Verification

Verify successful download and computer name assignment:
1. Observe the SIMATIC Manager download progress dialog; confirm it completes with 'Download completed successfully'.
2. Log onto the physical target OS station and open WinCC Explorer.
3. Open Computer Properties and verify that the computer name reflects the local machine name with status 'Active'.
4. Start WinCC Runtime on the target station and confirm process graphics and alarms operate normally.

Limitations and Operational Precautions

Workgroup Environments: If operating in a Windows Workgroup without a DNS server, identical entries for all ES, OS, and Client stations must be maintained in both the hosts and lmhosts files on every machine.
Redundant Server Downloads: When downloading redundant OS pairs, download the Standby Server first, verify runtime activation, and then download the Master Server to maintain uninterrupted operator coverage.
Security Software Interference: Third-party endpoint firewalls or antivirus software blocking TCP port 135 (RPC) or dynamic RPC ports will cause the remote rename script to time out.

Engineer FAQ

Why does the OS download sometimes succeed after multiple repeated attempts?

Intermittent success points to DNS caching delays or temporary NetBIOS broadcast timeouts. Fixing DNS reverse lookup eliminates the intermittent delays permanently.

What does Reset_WinCC.vbs do on the target station?

Reset_WinCC.vbs forcibly terminates hung WinCC background tasks, frees locked SQL Server handles, and releases shared memory segments without requiring a full Windows reboot.

Where can I find the detailed error log for failed OS downloads?

Download logs are written to the target station's project directory and the WinCC diagnostic folder under C:\Program Files (x86)\Siemens\WinCC\Diagnostics\Transfer.log.