diff --git a/build-aux/syntax-check.mk b/build-aux/syntax-check.mk
index 02ce879acc..d4d77a4308 100644
--- a/build-aux/syntax-check.mk
+++ b/build-aux/syntax-check.mk
@@ -823,9 +823,6 @@ http_sites += herp.derp
 # HTTP-only sites
 http_sites += 0pointer.de
 http_sites += mah.everybody.org
-http_sites += munin.projects.linpro.no
-http_sites += www.nimbusproject.org
-http_sites += www.sflow.net
 http_sites += etallen.com
 
 # dead sites
@@ -835,7 +832,6 @@ http_sites += www.javvin.com
 
 # 404 links
 http_sites += kerneltrap.org
-http_sites += www.microsoft.com
 
 http_re= ($(subst $(space),|,$(http_sites)))
 
diff --git a/docs/apps.rst b/docs/apps.rst
index 4d8c87d34d..1a25c0a21e 100644
--- a/docs/apps.rst
+++ b/docs/apps.rst
@@ -154,7 +154,7 @@ Infrastructure as a Service (IaaS)
    software platform that is open source and AWS-compatible. Eucalyptus
    uses libvirt virtualization API to directly interact with Xen and KVM
    hypervisors.
-`Nimbus <http://www.nimbusproject.org>`__
+`Nimbus <https://www.nimbusproject.org/>`__
    Nimbus is an open-source toolkit focused on providing
    Infrastructure-as-a-Service (IaaS) capabilities to the scientific
    community. It uses libvirt for communication with all KVM and Xen
@@ -224,14 +224,14 @@ Monitoring
    for each guest without installing collectd on the guest systems. For
    a full description, please refer to the libvirt section in the
    collectd.conf(5) manual page.
-`Host sFlow <https://www.sflow.net/>`__
+`Host sFlow <https://sflow.net/>`__
    Host sFlow is a lightweight agent running on KVM hypervisors that
    links to libvirt library and exports standardized cpu, memory,
    network and disk metrics for all virtual machines.
 `Munin <https://honk.sigxcpu.org/projects/libvirt/#munin>`__
    The plugins provided by Guido Günther allow to monitor various things
    like network and block I/O with
-   `Munin <http://munin.projects.linpro.no/>`__.
+   `Munin <https://munin-monitoring.org/>`__.
 `Nagios-virt <https://people.redhat.com/rjones/nagios-virt/>`__
    Nagios-virt is a configuration tool to add monitoring of your
    virtualised domains to `Nagios <https://www.nagios.org/>`__. You can
diff --git a/docs/drvhyperv.rst b/docs/drvhyperv.rst
index 17d620f29c..1760cc1fdb 100644
--- a/docs/drvhyperv.rst
+++ b/docs/drvhyperv.rst
@@ -9,7 +9,7 @@ The libvirt Microsoft Hyper-V driver can manage Hyper-V 2012 R2 and newer.
 Project Links
 -------------
 
--  The `Microsoft Hyper-V <http://www.microsoft.com/hyper-v-server/>`__
+-  The `Microsoft Hyper-V <https://docs.microsoft.com/en-us/windows-server/virtualization/hyper-v/hyper-v-on-windows-server>`__
    hypervisor
 
 Connections to the Microsoft Hyper-V driver