diff --git a/build.gradle b/build.gradle
index b58471174552cdde730a4a132f9441a711a66574..eff3cba8cf12b7d86c1f0580cfc787b5e9f2a539 100644
--- a/build.gradle
+++ b/build.gradle
@@ -7,8 +7,8 @@ wrapper {
 
 project.ext {
 	targetRepositories = [
-		"http://download.eclipse.org/releases/luna/",
-		"http://rodin-b-sharp.sourceforge.net/updates",
+		"https://download.eclipse.org/releases/luna/",
+		"https://rodin-b-sharp.sourceforge.net/updates",
 		"https://www3.hhu.de/stups/buildlibs/org.rodinp.dev/",
 	]
 
diff --git a/de.prob.core/prob_target.target b/de.prob.core/prob_target.target
index 4aa34f21d4b8db982c2ca6c63b4e5f7977b4eb93..33d292b13f734102b412c11b6355589979a10dd5 100644
--- a/de.prob.core/prob_target.target
+++ b/de.prob.core/prob_target.target
@@ -4,7 +4,7 @@
 <locations>
 <location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 <unit id="org.eclipse.gef.sdk.feature.group" version="3.9.101.201408150207"/>
-<repository location="http://download.eclipse.org/releases/luna"/>
+<repository location="https://download.eclipse.org/releases/luna"/>
 </location>
 <location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 <unit id="org.eventb.ide.feature.group" version="3.3.0.201704022034-f9fbb0d"/>
@@ -13,7 +13,7 @@
 </location>
 <location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 <unit id="org.eventb.theory.feature.feature.group" version="4.0.0.RC1"/>
-<repository location="http://rodin-b-sharp.sourceforge.net/updates/"/>
+<repository location="https://rodin-b-sharp.sourceforge.net/updates/"/>
 </location>
 </locations>
 </target>
\ No newline at end of file
diff --git a/tycho_build.gradle b/tycho_build.gradle
index c935ad6046d1b362cd16380f98fec84746814ebb..9f97ae1b672c4be7accdba73a91c79a5d643a158 100644
--- a/tycho_build.gradle
+++ b/tycho_build.gradle
@@ -106,7 +106,7 @@ try {
 try {
 	targetRepositories = targetRepositories
 } catch (MissingPropertyException e) {
-	project.ext.targetRepositories = ["http://download.eclipse.org/releases/luna/"]
+	project.ext.targetRepositories = ["https://download.eclipse.org/releases/luna/"]
 }
 
 try {