How to Change the Default Project Language in SIMATIC PCS 7 and STEP 7 Multiprojects

To change the default project language of a subproject within a SIMATIC PCS 7 Multiproject (for example, converting a project inadvertently created in Dutch to English US), engineers must navigate Windows non-Unicode codepage rules. In STEP 7 Classic, the 'Set project language to English' option in 'Language for Display Devices' is disabled once initialized. Furthermore, because Western European languages (Dutch, German, English, French) share the identical Windows ANSI Codepage (Windows-1252), performing a standard 'Save As' does not prompt to adapt the language. The verified resolution requires temporarily setting the Windows 'Language for non-Unicode programs' to a different codepage language (e.g., Russian Windows-1251), executing 'File -> Save As' on the individual part-project to adopt the new language, reverting Windows to English (US), and performing a final 'Save As' to establish English (US) as the permanent project language.

The Architecture of Project Languages in STEP 7 Classic

In SIMATIC PCS 7 and STEP 7 Classic, language handling operates across three distinct functional layers:

GUI Language: The display language of SIMATIC Manager dialogs, menus, and help files (e.g., English, German, French).
Language for Display Devices: The multilingual dictionary used for WinCC alarm texts, block comments, and operator prompts managed via the Text Library.
Project Language (Code Page): The underlying character encoding language assigned to the project database when it was originally created in Windows.

While GUI languages and display device texts can be added or switched freely at any time, the Project Language is permanently stamped into the project database headers based on the active Windows regional settings of the engineering PC at the moment of project creation.

Why the Default Project Language Becomes Locked

In SIMATIC Manager, when an engineer navigates to Options -> Language for display devices -> Add/Delete Languages, Set Default Language:
* The checkbox 'Set project language to...' is permanently greyed out.
* STEP 7 does not permit directly re-stamping the primary project language while the database is mounted, because doing so could lead to string character corruption in ladder logic, symbol comments, and CFC chart names.
* If a subproject was created on a workstation configured with Dutch regional settings, that subproject permanently reports Dutch as its project language, even if all text strings inside the project are typed in English.

The Shared Codepage Dilemma: Western European Languages (Windows-1252)

Siemens documentation states that executing File -> Save As... on a project will prompt:
'Do you want to adopt the project language to the current Windows language?'

However, engineers attempting to switch from Dutch to English (US) discover that this prompt never appears:
* The Root Cause: Windows assigns the exact same ANSI Codepage (Windows-1252) to English, Dutch, German, French, Spanish, and Italian.
* Because the source codepage (Dutch / 1252) is mathematically identical to the target codepage (English / 1252), STEP 7's database engine determines that no codepage conversion is necessary and silently preserves the existing Dutch project language header.

The Two-Step Codepage Re-adaptation Procedure via 'Save As'

To force SIMATIC Manager to update the project language header to English (US), execute this verified two-step conversion:

Step 1: Force a Codepage Discrepancy

In Windows Control Panel, open Region and Language -> Administrative.
Under Language for non-Unicode programs, click Change system locale.
Select a language utilizing a different codepage—such as Russian (Windows-1251) or Greek (Windows-1253).
Restart the computer as prompted by Windows.

Step 2: Perform the Intermediate 'Save As'

Launch SIMATIC Manager.
Open the individual part-project (not the entire multiproject).
In the menu bar, execute File -> Save As....
Select a new folder name.
Upon saving, SIMATIC Manager detects the codepage mismatch and prompts:
'The project language differs from your Windows language. Do you want to adopt the project language?'
Click Yes. The project language is now stamped as Russian.

Step 3: Revert to English (US) and Execute Final 'Save As'

Return to Windows Region settings; change the system locale to English (United States). Restart the PC.
Open the intermediate project in SIMATIC Manager.
Execute File -> Save As... once more.
When prompted to adopt the project language, click Yes.
The project language is now permanently and cleanly established as English (United States).

Project Language Setting Methods and Compatibility Matrix

The following table summarizes the methods for handling project language discrepancies in PCS 7:

MethodFeasibilityCodepage ImpactResulting Project LanguageRecommended Use Case'Language for Display Devices'Direct GUINone (Disabled)Unchanged (Greyed out)Cannot change project languageDirect 'Save As' (Dutch -> US)Direct GUIZero (Same Codepage 1252)Unchanged (Dutch)Fails due to identical codepageTwo-Step Codepage Re-adaptation100% VerifiedForces prompt via 1251English (United States)Approved permanent migration'Can be opened under any locale'WorkaroundBypasses checkUnchanged (Dutch)Temporary quick fix for opening

Executing the two-step codepage conversion eliminates project language mismatches permanently.

Verification

To verify that the project language has been successfully converted:
1. In SIMATIC Manager, right-click the converted part-project -> Object Properties.
2. Under the General tab, inspect the Project Language field: Confirm that it explicitly reads English (United States).
3. In the Multiproject view, confirm that all constituent AS and OS projects now display matching language attributes.
4. Open CFC and HW Config; confirm that all symbols, comments, and block parameters render without font distortion.

Limitations and Operational Precautions

Always perform a full project backup before changing Windows system locales or executing codepage reorganizations.
Execute the 'Save As' operation on the individual part-project; saving the entire multiproject monolithically may bypass part-project language adaptation prompts.
If the project contains custom non-standard characters (e.g., Cyrillic or Asian characters), verify that comments are not corrupted during codepage conversion.
Check the box 'Can be opened under any Windows language settings' in project properties to prevent future opening lockouts on international engineering laptops.

Engineer FAQ

Does having one project in Dutch cause errors during runtime or compilation?

No. In most cases, having a Western European language mismatch does not break CFC compilation or WinCC runtime, provided the project property 'Can be opened under any Windows language settings' is enabled. However, it can cause text library confusion during multi-user engineering.

Why is STEP 7 Classic not fully Unicode?

STEP 7 Classic (V5.x) was architected prior to universal Unicode adoption and relies on Windows ANSI code pages. Modern Siemens TIA Portal is fully Unicode-native, but PCS 7 retains STEP 7 Classic architecture.

What does 'Can be opened under any Windows language settings' do?

This property tells SIMATIC Manager to bypass the startup check comparing the project's codepage with the active Windows system locale, preventing error popups when opening projects internationally.