diff --git a/user-guide/thunderbird_for_o365.md b/user-guide/thunderbird_for_o365.md
index cebc44c6..0733989f 100644
--- a/user-guide/thunderbird_for_o365.md
+++ b/user-guide/thunderbird_for_o365.md
@@ -27,6 +27,10 @@ Then open the hamburger menu at the top left and select "Settings".
 
 There type `certificate` into the search box at the top left. Then press below the "Manage Certificates..." button.
 
+![Search for Certificate Settings](thunderbird_for_o365/thunderbird02b_certificate_dialog.png)
+
+Open the "Authorities" tab.
+
 ![Search for Certificate Settings](thunderbird_for_o365/thunderbird03_certificate_import.png)
 
 Here click on "Import..." and then select the previously downloaded and unpacked file "cert_PSI_FW_SSL_Scanner_TRUST.crt".
diff --git a/user-guide/thunderbird_for_o365/thunderbird02b_certficate_dialog.png b/user-guide/thunderbird_for_o365/thunderbird02b_certficate_dialog.png
new file mode 100644
index 00000000..9b09cd67
Binary files /dev/null and b/user-guide/thunderbird_for_o365/thunderbird02b_certficate_dialog.png differ