diff --git a/workspace/Dockerfile-56 b/workspace/Dockerfile-56
index b5756a5..7d8daea 100644
--- a/workspace/Dockerfile-56
+++ b/workspace/Dockerfile-56
@@ -540,9 +540,12 @@ RUN if [ ${INSTALL_LINUXBREW} = true ]; then \
 ARG INSTALL_MSSQL=false
 ENV INSTALL_MSSQL ${INSTALL_MSSQL}
 
-RUN if [ ${INSTALL_MSSQL} = true ]; then \
+RUN set -eux; if [ ${INSTALL_MSSQL} = true ]; then \
     apt-get -y install php5.6-sybase freetds-bin freetds-common libsybdb5 \
+    && echo "extension=mssql.so" > /etc/php/5.6/cli/conf.d/20-mssql.ini \
     && echo "extension=pdo_dblib.so" > /etc/php/5.6/cli/conf.d/20-pdo_dblib.ini \
+    && php -m | grep -q 'mssql' \
+    && php -m | grep -q 'pdo_dblib' \
 ;fi
 
 #####################################
diff --git a/workspace/Dockerfile-70 b/workspace/Dockerfile-70
index 340afef..c2aa3c9 100644
--- a/workspace/Dockerfile-70
+++ b/workspace/Dockerfile-70
@@ -536,7 +536,7 @@ RUN if [ ${INSTALL_LINUXBREW} = true ]; then \
 ARG INSTALL_MSSQL=true
 ENV INSTALL_MSSQL ${INSTALL_MSSQL}
 
-RUN if [ ${INSTALL_MSSQL} = true ]; then \
+RUN set -eux; if [ ${INSTALL_MSSQL} = true ]; then \
     #####################################
     #  The following steps were taken from
     #  https://github.com/Microsoft/msphpsql/wiki/Install-and-configuration
@@ -563,6 +563,8 @@ RUN if [ ${INSTALL_MSSQL} = true ]; then \
     locale-gen && \
     echo "extension=sqlsrv.so"     > /etc/php/7.0/cli/conf.d/20-sqlsrv.ini && \
     echo "extension=pdo_sqlsrv.so" > /etc/php/7.0/cli/conf.d/20-pdo_sqlsrv.ini \
+    && php -m | grep -q 'sqlsrv' \
+    && php -m | grep -q 'pdo_sqlsrv' \
 ;fi
 
 #####################################
diff --git a/workspace/Dockerfile-71 b/workspace/Dockerfile-71
index e7f80cf..2df347c 100644
--- a/workspace/Dockerfile-71
+++ b/workspace/Dockerfile-71
@@ -536,7 +536,7 @@ RUN if [ ${INSTALL_LINUXBREW} = true ]; then \
 ARG INSTALL_MSSQL=false
 ENV INSTALL_MSSQL ${INSTALL_MSSQL}
 
-RUN if [ ${INSTALL_MSSQL} = true ]; then \
+RUN set -eux; if [ ${INSTALL_MSSQL} = true ]; then \
     #####################################
     #  The following steps were taken from
     #  https://github.com/Microsoft/msphpsql/wiki/Install-and-configuration
@@ -563,6 +563,8 @@ RUN if [ ${INSTALL_MSSQL} = true ]; then \
     locale-gen && \
     echo "extension=sqlsrv.so"     > /etc/php/7.1/cli/conf.d/20-sqlsrv.ini && \
     echo "extension=pdo_sqlsrv.so" > /etc/php/7.1/cli/conf.d/20-pdo_sqlsrv.ini \
+    && php -m | grep -q 'sqlsrv' \
+    && php -m | grep -q 'pdo_sqlsrv' \
 ;fi
 
 #####################################
diff --git a/workspace/Dockerfile-72 b/workspace/Dockerfile-72
index f2b1cc5..c4cfa8b 100644
--- a/workspace/Dockerfile-72
+++ b/workspace/Dockerfile-72
@@ -536,7 +536,7 @@ RUN if [ ${INSTALL_LINUXBREW} = true ]; then \
 ARG INSTALL_MSSQL=false
 ENV INSTALL_MSSQL ${INSTALL_MSSQL}
 
-RUN if [ ${INSTALL_MSSQL} = true ]; then \
+RUN set -eux; if [ ${INSTALL_MSSQL} = true ]; then \
     #####################################
     #  The following steps were taken from
     #  https://github.com/Microsoft/msphpsql/wiki/Install-and-configuration
@@ -563,6 +563,8 @@ RUN if [ ${INSTALL_MSSQL} = true ]; then \
     locale-gen && \
     echo "extension=sqlsrv.so"     > /etc/php/7.2/cli/conf.d/20-sqlsrv.ini && \
     echo "extension=pdo_sqlsrv.so" > /etc/php/7.2/cli/conf.d/20-pdo_sqlsrv.ini \
+    && php -m | grep -q 'sqlsrv' \
+    && php -m | grep -q 'pdo_sqlsrv' \
 ;fi
 
 #####################################