diff --git a/src/modules/bootloader/main.py b/src/modules/bootloader/main.py
index 03fdb0c5b..3e384a018 100644
--- a/src/modules/bootloader/main.py
+++ b/src/modules/bootloader/main.py
@@ -474,6 +474,14 @@ def run():
             libcalamares.utils.warning( "EFI system, but nothing mounted on {!s}".format(efi_system_partition) )
             return None
 
-    prepare_bootloader(fw_type)
+    try:
+        prepare_bootloader(fw_type)
+    except subprocess.CalledProcessError as e:
+        libcalamares.utils.warning(str(e))
+        libcalamares.utils.debug("stdout:" + str(e.stdout))
+        libcalamares.utils.debug("stderr:" + str(e.stderr))
+        return (_("Bootloader installation error"),
+                _("The bootloader could not be installed. The installation command <pre>{!s}</pre> returned error code {!s}.")
+                .format(e.cmd, e.returncode))
 
     return None
diff --git a/src/modules/fstab/main.py b/src/modules/fstab/main.py
index b6d7a4b2a..61f6b0e9f 100644
--- a/src/modules/fstab/main.py
+++ b/src/modules/fstab/main.py
@@ -372,15 +372,23 @@ def run():
             root_btrfs = (root_partitions[0] == "btrfs") if root_partitions else False
             if root_btrfs:
                 partitions.append( dict(fs="swap", mountPoint=None, claimed=True, device="/swap/swapfile", uuid=None) )
-            else:    
+            else:
                 partitions.append( dict(fs="swap", mountPoint=None, claimed=True, device="/swapfile", uuid=None) )
         else:
             swap_choice = None
 
     libcalamares.job.setprogress(0.1)
-    mount_options = conf["mountOptions"]
+    mount_options = conf.get("mountOptions", {})
     ssd_extra_mount_options = conf.get("ssdExtraMountOptions", {})
     crypttab_options = conf.get("crypttabOptions", "luks")
+
+    # We rely on mount_options having a default; if there wasn't one,
+    # bail out with a meaningful error.
+    if not mount_options:
+        return (_("Configuration Error"),
+                _("No <pre>{!s}</pre> configuration is given for <pre>{!s}</pre> to use.")
+                .format("mountOptions", "fstab"))
+
     generator = FstabGenerator(partitions,
                                root_mount_point,
                                mount_options,
diff --git a/src/modules/packages/main.py b/src/modules/packages/main.py
index c3cc2ad7d..9be079dac 100644
--- a/src/modules/packages/main.py
+++ b/src/modules/packages/main.py
@@ -579,11 +579,27 @@ def run():
 
     update_db = libcalamares.job.configuration.get("update_db", False)
     if update_db and libcalamares.globalstorage.value("hasInternet"):
-        pkgman.update_db()
+        try:
+            pkgman.update_db()
+        except subprocess.CalledProcessError as e:
+            libcalamares.utils.warning(str(e))
+            libcalamares.utils.debug("stdout:" + str(e.stdout))
+            libcalamares.utils.debug("stderr:" + str(e.stderr))
+            return (_("Package Manager error"),
+                    _("The package manager could not prepare updates. The command <pre>{!s}</pre> returned error code {!s}.")
+                    .format(e.cmd, e.returncode))
 
     update_system = libcalamares.job.configuration.get("update_system", False)
     if update_system and libcalamares.globalstorage.value("hasInternet"):
-        pkgman.update_system()
+        try:
+            pkgman.update_system()
+        except subprocess.CalledProcessError as e:
+            libcalamares.utils.warning(str(e))
+            libcalamares.utils.debug("stdout:" + str(e.stdout))
+            libcalamares.utils.debug("stderr:" + str(e.stderr))
+            return (_("Package Manager error"),
+                    _("The package manager could not update the system. The command <pre>{!s}</pre> returned error code {!s}.")
+                    .format(e.cmd, e.returncode))
 
     operations = libcalamares.job.configuration.get("operations", [])
     if libcalamares.globalstorage.contains("packageOperations"):
@@ -603,11 +619,18 @@ def run():
     for entry in operations:
         group_packages = 0
         libcalamares.utils.debug(pretty_name())
-        run_operations(pkgman, entry)
+        try:
+            run_operations(pkgman, entry)
+        except subprocess.CalledProcessError as e:
+            libcalamares.utils.warning(str(e))
+            libcalamares.utils.debug("stdout:" + str(e.stdout))
+            libcalamares.utils.debug("stderr:" + str(e.stderr))
+            return (_("Package Manager error"),
+                    _("The package manager could make changes to the installed system. The command <pre>{!s}</pre> returned error code {!s}.")
+                    .format(e.cmd, e.returncode))
 
     mode_packages = None
 
     libcalamares.job.setprogress(1.0)
-    libcalamares.utils.debug(pretty_name())
 
     return None