Resolving ProTool Error 724:8 Open Object Failed on Windows 7

Problem Summary

Engineers maintaining legacy HMI configurations built with Siemens ProTool/Pro V6.0 commonly encounter error 724:8 with the message "OM OLE-Interface: Could not activate ProTool" when launching ProTool from SIMATIC Manager on Windows 7 64-bit systems. The HMI configuration editor fails to start through the SIMATIC Manager shell even though ProTool itself launches correctly when run directly from its desktop shortcut or Start menu entry.

This reference documents the root cause of the failure, the supported workarounds (compatibility mode, Windows XP Mode, full virtual machines, and DCOM permission changes), and the long-term migration path to WinCC Flexible 2008 SP5 and TIA Portal WinCC.

Technical Background: ProTool Lifecycle and OLE Integration

ProTool/Pro V6.0 was Siemens' HMI configuration suite for the OP panel family (OP3, OP7, OP17, OP27, OP37, OP170, OP270, OP370) and the Multi Panel (MP) family up through MP370. It shipped alongside STEP 7 V5.x and integrated with SIMATIC Manager through COM/OLE automation interfaces. When you right-click an HMI object in SIMATIC Manager and choose Open Object, the manager calls a registered COM class ID that activates the ProTool executable as an out-of-process server and passes the project handle.

The relevant COM activation path uses DCOM (Distributed COM). When a 32-bit COM server such as ProTool is registered on a 64-bit Windows host, the activation request must traverse the WOW64 surrogate layer. If the COM security descriptor, surrogate process identity, or executable compatibility flags are not configured, the COM runtime returns error class 0x724 (decimal 1828) to the calling process, which SIMATIC Manager surfaces as the string (724:8).

Root Cause of Error 724:8 on Windows 7

Three interacting root causes produce the 724:8 failure:

1. OS not released for ProTool. Siemens Entry ID 8795248 lists ProTool V6.0 SP3 as released only for Windows 2000 Professional and Windows XP Professional. Windows 7 (released October 2009) postdates ProTool development (final SP3 shipped 2004), so Siemens never validated the COM activation chain on Windows 7.
2. WOW64 / OLE surrogate mismatch. On Windows 7 64-bit, the default OLE surrogate for legacy 32-bit servers differs from Windows XP behaviour. Activation succeeds when the executable is launched directly but fails when invoked via COM because the surrogate cannot load the 32-bit type library in the expected context.
3. User Account Control (UAC) COM isolation. UAC, introduced in Vista and retained in Windows 7, runs non-elevated COM activations in a filtered access token. ProTool's COM object registers an AppID whose launch permission does not include the filtered token identity, and Windows 7 rejects the activation request with HRESULT 0x80070005 mapped into ProTool error class 724.

When ProTool.exe is launched directly, none of these three layers intervene; the editor starts normally and you bypass COM activation entirely. This is why engineers consistently report that the standalone editor works but the SIMATIC Manager integration does not.

Affected Versions, Panels, and Software Pairings

Panels configured with ProTool include the OP3, OP7, OP17, OP27, OP37, OP170 series, OP270 series, OP370 series, and the Multi Panel MP170, MP270, MP370. These can only be reconfigured with ProTool or with WinCC Flexible after project migration; TIA Portal does not support the legacy OP panel family at all.

The standard STEP 7 / ProTool pairings are STEP 7 V5.3 + ProTool V6.0 SP2/SP3, and STEP 7 V5.4 + ProTool V6.0 SP3. Avoid mixing newer STEP 7 versions (V5.5) with ProTool V6.0 SP3 because the SIMATIC Manager integration paths differ slightly and the COM activation can fail for a different reason than 724:8.

Pre-Installation Checklist

Before applying any workaround, complete the following:

1. Verify the ProTool version installed. Start ProTool.exe standalone, click Help → About, and record the exact build (for example, V6.0 SP3 HF7).
2. Verify the STEP 7 version installed. Open SIMATIC Manager and read the title bar; confirm a supported pairing from the table above.
3. Confirm the Windows 7 edition. XP Mode is available only on Windows 7 Professional, Enterprise, and Ultimate. Home Premium and Starter do not include XP Mode.
4. Confirm the user account has local administrator rights. Standard users cannot re-register COM classes or modify DCOM permissions.
5. Back up the project directory (*.pdb, *.s5p, *.s7p, *.s5z, *.s7z), the Siemens\Automation\ folder, and the registry hive HKLM\SOFTWARE\Siemens\Automation.
6. Record the ProTool authorization key (USB dongle serial, parallel port key, or hard-disk license).
7. Note any custom COM DLLs registered by add-on tools (e.g., third-party OPC bridges) because re-registering ProToolOle.dll can disturb them.

Workarounds for Error 724:8

Four workarounds are field-proven, listed from least invasive to most invasive. Pick the lightest one that satisfies your environment.

Workaround A: Windows 7 Compatibility Mode for ProTool.exe

This is the lightest-weight fix. Set the ProTool executable to run in Windows XP SP3 compatibility. On 32-bit Windows 7 this frequently resolves 724:8; on 64-bit Windows 7 it is necessary but often not sufficient.

1. Locate ProTool.exe. Default path on STEP 7 V5.4: C:\Program Files\Siemens\Automation\ProTool\ProTool.exe. On 64-bit Windows 7 it remains under Program Files (x86)\Siemens\Automation\ProTool\ProTool.exe.
2. Right-click ProTool.exe and choose Properties.
3. Open the Compatibility tab.
4. Check Run this program in compatibility mode for: and select Windows XP (Service Pack 3).
5. Check Run this program as an administrator only if the host enforces UAC and ProTool needs write access to Program Files.
6. Click Change settings for all users so the flag applies to the system-wide launcher invoked by COM, not just the interactive user.
7. Click Apply and OK.
8. Repeat for ProToolRT.exe and ProToolCS.exe if installed.

Workaround B: Windows XP Mode (Virtual PC)

For systems where compatibility mode does not clear error 724:8, run STEP 7 + ProTool inside Windows XP Mode. This is the configuration Siemens implicitly recommends by continuing to support Windows XP as the only released platform.

Prerequisites:

• Windows 7 Professional, Enterprise, or Ultimate (XP Mode is not in Home Premium or Starter).
• At least 2 GB RAM dedicated to the XP virtual machine; 4 GB host RAM minimum recommended.
• 15 GB free disk for the XP Mode base VHD plus installed software.
• STEP 7 V5.4 / V5.5 installation media.
• ProTool V6.0 SP3 installation media with valid authorization.

Installation sequence:

1. Install Windows Virtual PC and Windows XP Mode. The host package enables the virtualization layer; XP Mode ships the licensed Windows XP SP3 VHD.
2. Launch Windows XP Mode from the Start menu. The first launch finalizes the XP setup and prompts for credentials.
3. Install STEP 7 V5.4 (or V5.5) inside the XP Mode VM. Do not install disk-resident licensing (e.g., USB dongle drivers) until the dongle driver is confirmed compatible with XP Mode USB passthrough.
4. Install ProTool V6.0 SP3. During install select Integration with STEP 7 so the SIMATIC Manager shell registers the correct COM objects.
5. Copy project files into the VM. Use the VM's mapped host drive (default \\tsclient\C) or share a host folder through the VM's Tools menu.
6. Verify integration by launching SIMATIC Manager inside the VM, opening the project, right-clicking the HMI station, and selecting Open Object. ProTool must launch without error 724:8.

USB dongle passthrough: If the license is bound to a USB dongle (Sentinel, WIBU, CodeMeter), attach the dongle to the host before launching XP Mode. From the XP Mode window menu choose USB → Attach [Device Name]. Confirm the dongle driver installs inside XP. If the dongle is not visible, close XP Mode, attach the dongle, then restart XP Mode; XP Mode captures the USB topology only at VM startup.

Workaround C: Full Windows XP / Windows 2000 VM (VMware, VirtualBox, Hyper-V)

For non-Microsoft hypervisors or for Windows 7 Home Premium (no XP Mode), install a full Windows XP Professional SP3 or Windows 2000 Professional guest.

If 724:8 still appears inside a clean VM, the COM classes were not registered. From an elevated command prompt inside the guest:

cd "C:\Program Files\Siemens\Automation\ProTool"
regsvr32 /u ProToolOle.dll
regsvr32 ProToolOle.dll

cd "C:\Program Files\Siemens\Automation\SIMATIC Manager"
regsvr32 S7HEX2FX.DLL
regsvr32 S7HSPSVX.DLL

Reboot the VM and retest the SIMATIC Manager integration.

Workaround D: Run SIMATIC Manager as Administrator (32-bit Windows 7)

On 32-bit Windows 7 the simplest fix is UAC elevation. Right-click S7HSP_SVX.EXE (the SIMATIC Manager launcher) in the Start menu, choose Properties → Compatibility, and check Run this program as an administrator. Apply for all users. Because ProTool inherits the token of the parent COM activation, elevating the SIMATIC Manager launcher cascades the elevated token into the COM activation, bypassing UAC isolation.

DCOM Permission Audit (dcomcnfg)

When compatibility fixes are insufficient, audit DCOM permissions for the ProTool AppID.

1. Open Component Services by running dcomcnfg from the Start menu search box.
2. Navigate to Console Root → Component Services → Computers → My Computer → DCOM Config.
3. Locate the entry whose AppID matches the ProTool COM class (look for ProTool or ProTool.Application in the Application Name column).
4. Right-click and choose Properties.
5. On the Security tab, edit Launch and Activation Permissions and ensure the launching user or group has Local Launch and Local Activation rights.
6. On the Identity tab, select The launching user. Selecting The interactive user can produce activation failures under UAC.
7. Click Apply and reboot.

Registry Locations to Verify

On Windows 7 64-bit, COM class registrations for 32-bit servers appear under the Wow6432Node mirror. Use regedit to verify both nodes; a missing entry under the native 64-bit node does not indicate an installation fault.

Verifying the Fix

1. Open SIMATIC Manager.
2. Open the project containing the legacy HMI station.
3. Right-click the HMI station → Open Object.
4. Confirm ProTool launches without error 724:8.
5. In ProTool, open File → Open and verify the same project file loads without "Project file is read-only" warnings.
6. Edit a tag, save, and download to the panel via ProSave to confirm round-trip integrity.

Long-Term Migration: From ProTool to WinCC Flexible and TIA Portal

Every project still on ProTool should be scheduled for migration to WinCC Flexible 2008 SP5. WinCC Flexible imports ProTool V6.0 SP3 projects directly without loss of screens, tags, or alarms, provided the migration runs on a Windows 7 host with the same STEP 7 install. The migration wizard is invoked from WinCC Flexible → Project → Migrate ProTool Project.

After migration, WinCC Flexible 2008 SP5 must run on Windows 7 SP1 or Server 2008 R2. Projects migrated to TIA Portal WinCC V13+ cannot target the legacy OP panels; they require the Comfort or Basic panel families (KTP, TP, MP). Confirm panel replacement before committing to a TIA migration, because returning to a ProTool-only target after a TIA migration is not supported.

Troubleshooting Matrix

Field-Commissioning Notes

When commissioning on site with a Windows 7 laptop and no VM available, install ProTool on a pre-prepared Windows XP image stored on a USB SSD. Configure the laptop BIOS to boot from USB, or use WinPE to image the SSD. This is the most reliable path for a 30-minute on-site intervention because it avoids every Windows 7 / COM edge case.

Always carry the original ProTool CD set with authorization disk; the ProTool V6.0 SP3 installer does not embed license keys. Authorizations are transferred with the Automation License Manager (ALM) and stored on a USB dongle, parallel port key, or hard disk. Parallel port keys are unreliable on Windows 7 even with driver compatibility mode; carry a USB dongle as the primary fallback.

For MPI/DP transfer between PC and panel, the PC Adapter (USB) is supported by ProTool on Windows 7 once the SIMATIC USB driver is installed. The legacy COM-port adapter is unreliable because Windows 7 reserves COM1 for debugging unless explicitly released.

Backup and Recovery Considerations

ProTool project databases are not version-controlled in the modern sense. Treat the project directory as the source of truth and maintain a Git or SVN mirror. The .pdb file is a binary database; diff tools can compare it but cannot merge concurrent edits.

Before any migration, export the project from ProTool using File → Export → ProTool Project as PKZIP archive. The archive is signed with a project checksum; if the file becomes corrupt, the checksum fails and the project cannot be imported into WinCC Flexible.

For automated backup, schedule a PowerShell job that copies the project directory to a network share, then commits the .pdb to a Git repository with a daily timestamp tag. Git LFS is not required because .pdb files are typically under 50 MB.

FAQ