Microsoft Exchange and Active Directory Blog
After renewing the Exchange backend certificate, frequent channel error messages may appear in the event log if the POP3 service of the Exchange server is used. The following two error messages may appear after the certificate has been changed: Source: Schannel Event ID: 36871 Level: Error Fatal error while creating the client credentials for TLS. The internal error status ... Read more
Microsoft today released new security updates for all Exchange Server versions that are still supported. The updates address a total of 3 vulnerabilities: CVE-2020-17083 | Microsoft Exchange Server Remote Code Execution Vulnerability CVE-2020-17084 | Microsoft Exchange Server Remote Code Execution Vulnerability CVE-2020-17085 | Microsoft Exchange Server Denial of Service Vulnerability As two of the vulnerabilities allow remote code execution, it is recommended to ... Read more
Here is another error that can lead to despair, as there are some suggestions for a solution on the net, but they didn't help me. I had to install Exchange 2016 CU 17 for a customer and, as many people know, .NET Framework 4.8 is required for this. However, as the customer still ... Read more
In a somewhat older article, I already mentioned InfluxDB, Grafana and Telegraf. Grafana makes it easy to create attractive dashboards for all kinds of systems. The three tools mentioned are often used for the dashboards, InfluxDB as a database for storing the metrics, Grafana and displaying the dashboards and Telegraf to ... Read more
I have just uploaded version 3.8 (code name Leslie). This is the first version that has a "code name" because Leslie (the Leslie) was kind enough to dig through the many lines of PowerShell code and found and reported some bugs. The following bug fixes are included in version 3.8: updatereport.ps1: The module showed the ... Read more
Yesterday, Microsoft released a new security update for Exchange Server 2013, 2016 and 2019. The update closes the vulnerability CVE-2020-16969. The vulnerability can be exploited with a specially crafted email, so the update should be installed promptly. The update is classified as "Important". Microsoft describes the vulnerability as follows: An information disclosure vulnerability exists in ... Read more
Originally I had given up the plan to write another white paper on the subject of "Exchange and certificates". However, there still seem to be very frequent problems with the configuration of certificates in connection with Exchange servers. There are already a few articles and scripts here, so now a comprehensive whitepaper on the subject will follow ... Read more
Microsoft has released new Cumulative Updates (CU) for Exchange 2016 and Exchange 2019 today: Exchange Server 2019 Cumulative Update 7 (KB4571787), VLSC Download Exchange Server 2016 Cumulative Update 18 (KB4571788), Download, The Exchange 2019 CU 7 is also already available for download via MyVisualStudio. Here is a list of the fixed issues: 4570248 "Get-CASMailbox" uses a ... Read more
Microsoft has released a security update for Exchange Server 2019 and Exchange 2016 to close a vulnerability classified as "critical". Specifically, it concerns the vulnerability CVE-2020-16875: A remote code execution vulnerability exists in Microsoft Exchange server due to improper validation of cmdlet arguments. An attacker who successfully exploited the vulnerability could run arbitrary code ... Read more
Once an Exchange 2019 server has been configured, an SSL certificate needs to be installed. To configure the certificate correctly, the hostnames that are relevant for the certificate must be determined. The following script reads the hostnames from the configured URLs of the virtual directories and displays the corresponding hostnames in the Exchange Management Shell ... Read more
