C# - Getting the full picture from WUAPI

Question

I am trying to collect an accurate picture of Windows Updates, specifically KB installations, on a number of different machines. I've tried a number of different pieces of code that I've found scattered about, but I still cannot seem to create an accurate picture of what is installed. By accurate, I mean that whatever I gather seems to be a subset of what is shown when I check the Windows Update History on the machine using the Windows UI! Can't seem to figure this out!

Here are a few things I've tried;

        UpdateSession uSession = new UpdateSession();

        IUpdateSearcher uSearcher = uSession.CreateUpdateSearcher();
        uSearcher.Online = false;

        ISearchResult sResult = uSearcher.Search("IsInstalled=1");

        foreach (IUpdate update in sResult.Updates)
        {
            foreach (string kbaid in update.KBArticleIDs)
            {
                txtAllUpdates.AppendText(kbaid + Environment.NewLine);
            }
        }

I also tried adding code within this same routine to gather all of the updates within the Bundled Updates field, like so;

        foreach (IUpdate update2 in update.BundledUpdates)
        {
            txtAllUpdates.AppendText("\t--> " + update2.Title + Environment.NewLine);
            foreach (string kbaid2 in update2.BundledUpdates)
            {
                string kbNo = GetKBNo(update2.Title.ToLower());
                txtAllUpdates.AppendText("\t\t" + kbNo);
            }
        }

I also tried looking at the Update History, but that provided me with yet another set of data - still not complete!

        UpdateSession updateSession = new UpdateSession();
        IUpdateSearcher updateSearcher = updateSession.CreateUpdateSearcher();
        int count = updateSearcher.GetTotalHistoryCount();
        MessageBox.Show("Total Count = " + count);
        IUpdateHistoryEntryCollection history = updateSearcher.QueryHistory(0, count);

        for (int i = 0; i < count; ++i)
        {
            txtAllUpdates.AppendText("\t\t\t" + history[i].Title);

        }

I also checked into some code that leverages the registry, but from what I've read, that's not the right way to do things. At this point, I'm performing a number of different queries, searching entries for "KB" references and building a list and removing duplicates, but I'm still not getting the same list I see on the screen! Even if this did work, it can't possibly be the right way to go - I feel like I must be missing something.

Finally, I tried to just get information on when updates were last checked for and installed - even that doesn't match up with what is displayed. I did this with the following code;

        var auc = new AutomaticUpdatesClass();

        DateTime? lastInstallationSuccessDateUtc = null;
        if (auc.Results.LastInstallationSuccessDate is DateTime)
            lastInstallationSuccessDateUtc = new DateTime(((DateTime)auc.Results.LastInstallationSuccessDate).Ticks, DateTimeKind.Utc);

        DateTime? lastSearchSuccessDateUtc = null;
        if (auc.Results.LastSearchSuccessDate is DateTime)
            lastSearchSuccessDateUtc = new DateTime(((DateTime)auc.Results.LastSearchSuccessDate).Ticks, DateTimeKind.Utc);

        lblInstall.Text += lastInstallationSuccessDateUtc.ToString();
        lblSearch.Text += lastSearchSuccessDateUtc.ToString();

Does anyone have some expertise in this area? Really want to get this done right!

Thanks for taking the time to read!

Respectfully, Marshall

Chrissy LeMaire · Answer 1 · 2022-08-04T14:37:04.950

All the various ways to find installed software is incomplete, so I used a variety of ways in Get-KbInstalledUpdate, which I describe as a:

Replacement for Get-Hotfix, Get-Package, searching the registry and searching CIM for updates

Though I haven't tried this way, which is essentially:

$session = New-Object -ComObject "Microsoft.Update.Session"
$updatesearcher = $session.CreateUpdateSearcher()
$count = $updatesearcher.GetTotalHistoryCount()
$updates = $updatesearcher.QueryHistory(0, $count)

C# - Getting the full picture from WUAPI

1 Answers1