On April 14, 2026 (the second Tuesday of the month, Microsoft's Patch Tuesday), Microsoft released cumulative updates for the still-supported client operating system versions of Windows 10 (with an ESU license) and Windows 11. Microsoft has also released security updates for supported Windows Server versions and for Office as well.
[German]On April 14, 2026, Microsoft released security updates for Windows clients and servers, for Office, and for other products. The security updates address 163 vulnerabilities (CVEs), 8 of which are critical; 2 of these were classified as zero-day vulnerabilities (one of which has been exploited).
[German]Microsoft acknowledged an issue with the reset feature in Windows 11 Enterprise LTSC 2024 on April 9, 2026. If the hotfix KB5079420 from March 10, 2026 (and possibly also the hotfix KB5077212 from February 10, 2026) has been installed, there may be issues with the reset function in Windows 11 Enterprise LTSC 2024. However, the information available to me is somewhat confusing and incomplete. Read more details within my German blog post [use site`s build-in translation to show it in English etc.]
[German]A few hours ago, I reported on a zero-day vulnerability in Adobe Reader. Simply opening a PDF file can be enough to take control of the system. Adobe has now confirmed the vulnerability (CVE-2026-34621) and released a security update to patch it. This should be installed within 72 hours.
[German]Another update from April 3, 2026, affecting Microsoft OneDrive users. On that date, Microsoft announced that starting in May 2026, files deleted from the OneDrive cloud will no longer appear in the local Recycle Bin. However, recovery via the OneDrive or SharePoint web Recycle Bin will still be possible.
[Sponsored Post]In the rapidly evolving IT world, choosing the right remote desktop software is critical for organizations that value security, ease of use and reliability. One provider of secure remote access that has been on the market since 2001 is ISL Online, which presents some considerations for choosing such software below. More ...
[German]Warning to users who use tools such as CPUID, HWMonitor, CPU-Z, etc. and updated it recently (between April 9, and April 10, 2026. The website where these tools were hosted and offered for download has fallen victim to a supply chain attack. As a result, malware was/is being distributed via downloads from the web server. Therefore, anyone who has recently downloaded tools such as CPUID, HWMonitor, CPU-Z, etc., from this website may have malware on their Windows system.
[German]A quick note for administrators of Microsoft 365 installations who have placed their users in the Semi-Annual Enterprise Channel (SAEC). This channel will be merged with the Monthly Enterprise Channel (MEC). Users will therefore be subjected to the flood of updates from Redmond on a monthly basis going forward. And for new MS 365 tenants, the Semi-Annual Enterprise Channel (SAEC) is already no longer selectable in the Microsoft 365 Admin Center. Further details may be read within my German blog [use build in translation to read the text].
[German]I received a report from a reader stating that the KB5085516 update for Windows 11 25H2 Pro is causing issues on the Windows desktop for this user. This affects how windows are displayed on the desktop, making it impossible to resize them or make other adjustments. German blog readers has confirmed this behavior. Details may be found at my German article [use build-in translation to read the text].
[German]A quick note to blog readers who use Veeam Backup 365. Back in November 2025, there were already issues with the integration between Veeam Backup and Microsoft 365 mailboxes. Now, a reader has once again reported the Veeam Backup issue with Microsoft 365 mailboxes to me. This time, the EWS migration planned for Exchange Online starting at the end of 2026 has already cast its shadow. Microsoft rolled out its code change on March 27, 2026, which affects Veeam Backup and leads to errors.
There was an issue sending emails in Outlook Classic when using a mailbox on outlook.com. This caused the operation to trigger an NDR error 0x80070005-0x0004dc-0x000524. The issue has since been resolved. I have added this information to the German post Outlook Classic: E-Mail senden scheitert mit 0x80070005-0x0004dc-0x000524 [use build in translation to read the article in your language].
MVP:
2013 – 2016
WIMVP:
2017 – 2020
