I am using Windows MSI API to update the Package Code of an MSI package. I can successfully retrieve the package code without issues. However, the MsiSummaryInfoSetProperty() call to set the new package code fails with error code 1627. One issue is that PID_REVNUMBER does not resolve to a known identifier, but PIDSI_REVNUMBER does. Both PID_REVNUMBER and PIDSI_REVNUMBER resolve to the same constant. Other than that, can you spot any issues in the code snippet below?

#pragma comment(lib, "msi.lib")

#include <iostream>
#include <windows.h>
#include "msi.h"
#include "msiquery.h"
#include "oaidl.h"

int main()
{
    UINT result;

    MSIHANDLE hDatabase = NULL;
    char msiPkg[] = "C:\mypkg.msi";
    result = MsiOpenDatabase(msiPkg, MSIDBOPEN_DIRECT, &hDatabase);
    if (result != ERROR_SUCCESS) {
        std::cerr << "Failed to open MSI database. Error: " << result << std::endl;
        return false;
    }

    // Get the summary information handle
    MSIHANDLE hSummaryInfo = NULL;
    result = MsiGetSummaryInformation(hDatabase, NULL, 0, &hSummaryInfo);
    if (result != ERROR_SUCCESS) {
        std::cerr << "Failed to get summary information. Error: " << result << std::endl;
        MsiCloseHandle(hDatabase);
        return false;
    }

    // Retrieve the package code
    char packageCode[39]; // GUIDs are 38 characters + null terminator
    DWORD packageCodeSize = sizeof(packageCode) / sizeof(packageCode[0]);
    result = MsiSummaryInfoGetProperty(hSummaryInfo, PIDSI_REVNUMBER, NULL, NULL, NULL, packageCode, &packageCodeSize);
    if (result != ERROR_SUCCESS) {
        std::cerr << "Failed to get package code. Error: " << result << std::endl;
        MsiCloseHandle(hSummaryInfo);
        MsiCloseHandle(hDatabase);
        return false;
    }
    std::cout << "Package code: " << packageCode << std::endl;

    // Set the new package code
    // https://learn.microsoft.com/en-us/windows/win32/msi/summary-information-stream-property-set
    // https://learn.microsoft.com/en-us/windows/win32/stg/the-summary-information-property-set
    char newPackageCode[] = "{B4CC3940-2CDD-4EFF-9B59-B7D6D838242E}";
    result = MsiSummaryInfoSetProperty(hSummaryInfo, PIDSI_REVNUMBER, VT_LPSTR, 0, NULL, newPackageCode);
    if (result != ERROR_SUCCESS) {
        std::cerr << "Failed to set package code. Error: " << result << std::endl;
        MsiCloseHandle(hSummaryInfo);
        MsiCloseHandle(hDatabase);
        return false;
    }

    // Persist changes to the summary information stream
    result = MsiSummaryInfoPersist(hSummaryInfo);
    if (result != ERROR_SUCCESS) {
        std::cerr << "Failed to persist summary information. Error: " << result << std::endl;
        MsiCloseHandle(hSummaryInfo);
        return false;
    }

    // Clean up
    MsiCloseHandle(hSummaryInfo);
    MsiCloseHandle(hDatabase);
}

• Replace the MsiSummaryInfoSetProperty() call with packageCode instead of newPackageCode
• Tried different GUID values for newPackageCode

The call still fails.