diff --git a/locale/en/LC_MESSAGES/vips.po b/locale/en/LC_MESSAGES/vips.po
index 4cb5fc00def8e0d0b716363e1f539795d97c1b24..21d573288188d38d67a896dd6309b1be34003097 100644
--- a/locale/en/LC_MESSAGES/vips.po
+++ b/locale/en/LC_MESSAGES/vips.po
@@ -6,7 +6,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: PACKAGE VERSION\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2021-06-09 17:57+0200\n"
+"POT-Creation-Date: 2021-06-10 15:38+0200\n"
 "PO-Revision-Date: 2011-12-07 13:49+0200\n"
 "Language: en\n"
 "MIME-Version: 1.0\n"
@@ -58,8 +58,8 @@ msgstr[0] "%d new worksheet"
 msgstr[1] "%d new worksheets"
 
 #: VipsPlugin.php:253 controllers/solutions.php:51
-#: controllers/solutions.php:157 controllers/solutions.php:1475
-#: controllers/solutions.php:1634
+#: controllers/solutions.php:157 controllers/solutions.php:1403
+#: controllers/solutions.php:1562
 msgid "Ergebnisse"
 msgstr "Results"
 
@@ -290,13 +290,13 @@ msgid_plural "Es wurden %d Gruppen angelegt."
 msgstr[0] "One group has been created."
 msgstr[1] "%d groups have been created."
 
-#: controllers/groups.php:469 controllers/solutions.php:788
-#: controllers/solutions.php:1391
+#: controllers/groups.php:469 controllers/solutions.php:716
+#: controllers/solutions.php:1319
 msgid "Nachname"
 msgstr "Family name"
 
-#: controllers/groups.php:469 controllers/solutions.php:788
-#: controllers/solutions.php:1391
+#: controllers/groups.php:469 controllers/solutions.php:716
+#: controllers/solutions.php:1319
 msgid "Vorname"
 msgstr "First name"
 
@@ -489,7 +489,7 @@ msgstr "Time has expired!"
 
 #: controllers/sheets.php:422 controllers/sheets.php:1184
 #: controllers/sheets.php:1702 controllers/sheets.php:1872
-#: controllers/solutions.php:1011
+#: controllers/solutions.php:939
 msgid "Zeichenwähler öffnen"
 msgstr "Show character picker"
 
@@ -510,7 +510,7 @@ msgstr ""
 "submit student solutions here."
 
 #: controllers/sheets.php:440 controllers/sheets.php:1190
-#: controllers/solutions.php:1013
+#: controllers/solutions.php:941
 msgid "Aufgabe bearbeiten"
 msgstr "Work on this task"
 
@@ -532,7 +532,7 @@ msgstr "Don't forget to save your input before leaving the page."
 
 #: controllers/sheets.php:464 controllers/sheets.php:1198
 #: controllers/sheets.php:1433 controllers/sheets.php:1855
-#: controllers/solutions.php:1037 controllers/solutions.php:1120
+#: controllers/solutions.php:965 controllers/solutions.php:1048
 #: lib/VipsAssignment.php:87 lib/VipsAssignment.php:143
 #: views/pool/list_exercises.php:49 views/sheets/copy_exercise_dialog.php:40
 msgid "Aufgabenblatt"
@@ -540,7 +540,7 @@ msgstr "Worksheet"
 
 #: controllers/sheets.php:591 controllers/sheets.php:619
 #: controllers/sheets.php:1707 controllers/solutions.php:390
-#: controllers/solutions.php:1016 controllers/solutions.php:1356
+#: controllers/solutions.php:944 controllers/solutions.php:1284
 #: views/pool/list_assignments.php:100
 #: views/sheets/list_assignments_list.php:132
 #: views/sheets/list_assignments_stud.php:97
@@ -596,7 +596,7 @@ msgstr "The block assignment has been saved."
 msgid "Die Aufgabenblätter wurden verschoben."
 msgstr "The worksheets have been moved."
 
-#: controllers/sheets.php:971 controllers/solutions.php:1317
+#: controllers/sheets.php:971 controllers/solutions.php:1245
 msgid ""
 "Die Klausur wurde zurückgesetzt und alle abgegebenen Lösungen archiviert."
 msgstr "The exam has been reset and all existing solutions have been archived."
@@ -618,8 +618,8 @@ msgstr "You can edit the description and answer options on this page."
 msgid "Neue Aufgabe erstellen"
 msgstr "Create new task"
 
-#: controllers/sheets.php:1201 controllers/solutions.php:1040
-#: controllers/solutions.php:1123 views/exercises/show_exercise_link.php:3
+#: controllers/sheets.php:1201 controllers/solutions.php:968
+#: controllers/solutions.php:1051 views/exercises/show_exercise_link.php:3
 #, php-format
 msgid "Aufgabe %d"
 msgstr "Task %d"
@@ -699,7 +699,7 @@ msgstr[0] "Worksheet %s was added with %d task."
 msgstr[1] "Worksheet %s was added with %d tasks."
 
 #: controllers/sheets.php:1909 controllers/sheets.php:1916
-#: controllers/solutions.php:1346
+#: controllers/solutions.php:1274
 msgid "Die Korrekturen wurden noch nicht freigegeben."
 msgstr "No task was graded or the grades have not been published."
 
@@ -773,7 +773,7 @@ msgstr ""
 msgid "Vips für Studierende sichtbar"
 msgstr "Vips is visible to students"
 
-#: controllers/sheets.php:2086 controllers/solutions.php:1022
+#: controllers/sheets.php:2086 controllers/solutions.php:950
 #: exercises/lti_exercise.php:111
 msgid "Links"
 msgstr "Links"
@@ -789,18 +789,18 @@ msgstr "This page lists the correction status of all your worksheets."
 msgid "Notenverteilung festlegen"
 msgstr "Grade distribution"
 
-#: controllers/solutions.php:158 controllers/solutions.php:1476
-#: controllers/solutions.php:1635 views/solutions/participants_overview.php:6
+#: controllers/solutions.php:158 controllers/solutions.php:1404
+#: controllers/solutions.php:1563 views/solutions/participants_overview.php:6
 msgid "Punkteübersicht"
 msgstr "Point overview"
 
-#: controllers/solutions.php:159 controllers/solutions.php:1477
-#: controllers/solutions.php:1636 views/solutions/participants_overview.php:28
+#: controllers/solutions.php:159 controllers/solutions.php:1405
+#: controllers/solutions.php:1564 views/solutions/participants_overview.php:28
 msgid "Notenübersicht"
 msgstr "Grade overview"
 
-#: controllers/solutions.php:160 controllers/solutions.php:1478
-#: controllers/solutions.php:1637
+#: controllers/solutions.php:160 controllers/solutions.php:1406
+#: controllers/solutions.php:1565
 msgid "Statistik"
 msgstr "Statistics"
 
@@ -819,7 +819,7 @@ msgstr "The visibility settings have been saved."
 msgid "Teilnehmer"
 msgstr "Participants"
 
-#: controllers/solutions.php:361 controllers/solutions.php:1399
+#: controllers/solutions.php:361 controllers/solutions.php:1327
 #: views/solutions/participants_overview.php:109
 msgid "Summe"
 msgstr "Total"
@@ -863,14 +863,14 @@ msgstr "Publish into gradebook"
 msgid "Punktetabelle exportieren"
 msgstr "Export score table"
 
-#: controllers/solutions.php:421
-msgid "Lösungen der Teilnehmer exportieren"
-msgstr "Export all solutions"
-
-#: controllers/solutions.php:426
+#: controllers/solutions.php:423
 msgid "Abgabeprotokolle exportieren"
 msgstr "Export submission logs"
 
+#: controllers/solutions.php:428
+msgid "Lösungen der Teilnehmer exportieren"
+msgstr "Export all solutions"
+
 #: controllers/solutions.php:431 views/solutions/assignment_solutions.php:186
 msgid "Abgegebene Dateien herunterladen"
 msgstr "Download attached files"
@@ -924,155 +924,150 @@ msgstr "%sTasks shown in red%s have not been graded yet."
 msgid "%sAusgegraute Aufgaben%s wurden vom Teilnehmer nicht bearbeitet."
 msgstr "%sTasks shown in grey%s have not been submitted by the student."
 
-#: controllers/solutions.php:551 controllers/solutions.php:610
-#: controllers/solutions.php:692 exercises/jv_exercise.php:384
+#: controllers/solutions.php:555 controllers/solutions.php:614
+#: exercises/jv_exercise.php:384 exercises/tb_exercise.php:242
 msgid "ZIP-Archiv konnte nicht erzeugt werden."
 msgstr "Cannot create ZIP archive."
 
-#: controllers/solutions.php:567
+#: controllers/solutions.php:571
 #, php-format
 msgid "%s/Aufgabe %d/"
 msgstr "%s/Task %d/"
 
-#: controllers/solutions.php:618
+#: controllers/solutions.php:622
 #, php-format
 msgid "Aufgabe %d/"
 msgstr "Task %d/"
 
-#: controllers/solutions.php:652 controllers/solutions.php:683
-#: lib/vips_common.inc.php:490
-msgid "Sie haben keinen Zugriff auf diese Datei!"
-msgstr "You don't have access to this file!"
-
-#: controllers/solutions.php:750
+#: controllers/solutions.php:678
 msgid "Das Aufgabenblatt wurde in das Gradebook eingetragen."
 msgstr "The worksheet has been published in the gradebook."
 
-#: controllers/solutions.php:772
+#: controllers/solutions.php:700
 msgid "Das Aufgabenblatt wurde aus dem Gradebook gelöscht."
 msgstr "The worksheet has been removed from the gradebook."
 
-#: controllers/solutions.php:788
+#: controllers/solutions.php:716
 msgid "Kennung"
 msgstr "Account"
 
-#: controllers/solutions.php:788 views/solutions/show_assignment_log.php:9
+#: controllers/solutions.php:716 views/solutions/show_assignment_log.php:9
 msgid "Ereignis"
 msgstr "Event"
 
-#: controllers/solutions.php:789 views/solutions/show_assignment_log.php:12
+#: controllers/solutions.php:717 views/solutions/show_assignment_log.php:12
 msgid "Zeit"
 msgstr "Time"
 
-#: controllers/solutions.php:789 views/solutions/assignment_solutions.php:119
+#: controllers/solutions.php:717 views/solutions/assignment_solutions.php:119
 #: views/solutions/show_assignment_log.php:15
 msgid "IP-Adresse"
 msgstr "IP address"
 
-#: controllers/solutions.php:789 views/solutions/show_assignment_log.php:18
+#: controllers/solutions.php:717 views/solutions/show_assignment_log.php:18
 msgid "Rechnername"
 msgstr "Client hostname"
 
-#: controllers/solutions.php:789 views/solutions/show_assignment_log.php:21
+#: controllers/solutions.php:717 views/solutions/show_assignment_log.php:21
 msgid "Sitzungs-ID"
 msgstr "Session ID"
 
-#: controllers/solutions.php:867
+#: controllers/solutions.php:795
 #, php-format
 msgid "Es wurde %d Lösung korrigiert."
 msgid_plural "Es wurden %d Lösungen korrigiert."
 msgstr[0] "%d solution was graded."
 msgstr[1] "%d solutions were graded."
 
-#: controllers/solutions.php:1008
+#: controllers/solutions.php:936
 msgid ""
 "Sie können hier die Ergebnisse der Autokorrektur ansehen und Aufgaben "
 "manuell korrigieren."
 msgstr "This view is used to manually correct exercises."
 
-#: controllers/solutions.php:1024
+#: controllers/solutions.php:952
 msgid "Vorige unkorrigierte Aufgabe"
 msgstr "Previous uncorrected task"
 
-#: controllers/solutions.php:1030
+#: controllers/solutions.php:958
 msgid "Nächste unkorrigierte Aufgabe"
 msgstr "Next uncorrected task"
 
-#: controllers/solutions.php:1045
+#: controllers/solutions.php:973
 msgid "Versionen"
 msgstr "Versions"
 
-#: controllers/solutions.php:1046 views/solutions/edit_solution.php:83
+#: controllers/solutions.php:974 views/solutions/edit_solution.php:83
 #: views/solutions/view_solution.php:41
 msgid "nicht abgegeben"
 msgstr "not submitted"
 
-#: controllers/solutions.php:1047
+#: controllers/solutions.php:975
 #, php-format
 msgid "Aktuelle Version: %s"
 msgstr "Current version: %s"
 
-#: controllers/solutions.php:1056
+#: controllers/solutions.php:984
 #, php-format
 msgid "Version %s vom %s"
 msgstr "Version %s from %s"
 
-#: controllers/solutions.php:1080
+#: controllers/solutions.php:1008
 msgid "Die Korrekturen des Aufgabenblatts sind nicht freigegeben."
 msgstr "No task was graded or the grades have not been published."
 
-#: controllers/solutions.php:1151
+#: controllers/solutions.php:1079
 msgid "Die ausgewählte Lösung wurde als aktuelle Version gespeichert."
 msgstr "The selected solution was saved as the current version."
 
-#: controllers/solutions.php:1218
+#: controllers/solutions.php:1146
 #, php-format
 msgid "Sie haben Bonuspunkte vergeben (%s von %s)."
 msgstr "You assigned %d bonus points."
 
-#: controllers/solutions.php:1220
+#: controllers/solutions.php:1148
 #, php-format
 msgid "Sie haben eine negative Punktzahl eingegeben (%s von %s)."
 msgstr "You entered a negative amount of points (%s of %s)."
 
-#: controllers/solutions.php:1232
+#: controllers/solutions.php:1160
 msgid "Ihre Korrektur wurde gespeichert."
 msgstr "Your grade was saved."
 
-#: controllers/solutions.php:1288
+#: controllers/solutions.php:1216
 msgid "Der Abgabezeitpunkt liegt nach dem Ende der Klausur."
 msgstr "The specified due date is after the end time of the exam."
 
-#: controllers/solutions.php:1291
+#: controllers/solutions.php:1219
 msgid "Der Abgabezeitpunkt ist keine gültige Uhrzeit."
 msgstr "The specified due date is not a valid time."
 
-#: controllers/solutions.php:1320
+#: controllers/solutions.php:1248
 msgid ""
 "Die Teilnahme wurde zurückgesetzt und ggf. abgegebene Lösungen archiviert."
 msgstr ""
 "The exam has been reset for this user and any solutions have been archived."
 
-#: controllers/solutions.php:1352
+#: controllers/solutions.php:1280
 msgid ""
 "Sie können hier die Ergebnisse bzw. die Korrekturen ihrer Aufgaben ansehen."
 msgstr "This page lists all the results of the test."
 
-#: controllers/solutions.php:1391
+#: controllers/solutions.php:1319
 msgid "Matrikelnr."
 msgstr "Student registration number"
 
-#: controllers/solutions.php:1402 views/admin/edit_grades.php:13
+#: controllers/solutions.php:1330 views/admin/edit_grades.php:13
 #: views/solutions/participants_overview.php:116
 #: views/solutions/student_grade.php:6
 msgid "Note"
 msgstr "Grade"
 
-#: controllers/solutions.php:1411 views/solutions/participants_overview.php:126
+#: controllers/solutions.php:1339 views/solutions/participants_overview.php:126
 msgid "Maximalpunktzahl:"
 msgstr "Maximum number of points:"
 
-#: controllers/solutions.php:1413 views/exercises/edit_jv_exercise.php:27
+#: controllers/solutions.php:1341 views/exercises/edit_jv_exercise.php:27
 #: views/exercises/edit_jv_exercise.php:38
 #: views/exercises/edit_jv_exercise.php:55
 #: views/exercises/edit_jv_exercise.php:93
@@ -1080,21 +1075,21 @@ msgstr "Maximum number of points:"
 msgid "Gewichtung:"
 msgstr "Weight:"
 
-#: controllers/solutions.php:1469
+#: controllers/solutions.php:1397
 msgid "Notenliste.csv"
 msgstr "grades.csv"
 
-#: controllers/solutions.php:1472
+#: controllers/solutions.php:1400
 msgid ""
 "Diese Seite gibt einen Überblick über die von allen Teilnehmern erreichten "
 "Punkte und ggf. Noten."
 msgstr "This page displays a summary of all test results for this course."
 
-#: controllers/solutions.php:1482 controllers/solutions.php:1641
+#: controllers/solutions.php:1410 controllers/solutions.php:1569
 msgid "Liste im CSV-Format exportieren"
 msgstr "Export this list in CSV format"
 
-#: controllers/solutions.php:1577 views/config/pending_assignments.php:12
+#: controllers/solutions.php:1505 views/config/pending_assignments.php:12
 #: views/exercises/correct_jv_exercise.php:48
 #: views/exercises/edit_exercise.php:55 views/exercises/edit_jv_exercise.php:62
 #: views/exercises/edit_jv_exercise.php:99 views/pool/list_assignments.php:25
@@ -1107,37 +1102,37 @@ msgstr "Export this list in CSV format"
 msgid "Titel"
 msgstr "Title"
 
-#: controllers/solutions.php:1578 exercises/Exercise.php:106
+#: controllers/solutions.php:1506 exercises/Exercise.php:106
 #: exercises/Exercise.php:608 exercises/Exercise.php:629
 msgid "Aufgabe"
 msgstr "Task"
 
-#: controllers/solutions.php:1579
+#: controllers/solutions.php:1507
 msgid "Item"
 msgstr "Item"
 
-#: controllers/solutions.php:1580 views/solutions/statistics.php:15
+#: controllers/solutions.php:1508 views/solutions/statistics.php:15
 msgid "erreichbare Punkte"
 msgstr "achievable points"
 
-#: controllers/solutions.php:1581 views/solutions/statistics.php:18
+#: controllers/solutions.php:1509 views/solutions/statistics.php:18
 msgid "durchschn. Punkte"
 msgstr "average points"
 
-#: controllers/solutions.php:1582 views/solutions/statistics.php:21
+#: controllers/solutions.php:1510 views/solutions/statistics.php:21
 msgid "korrekte Lösungen"
 msgstr "correct solutions"
 
-#: controllers/solutions.php:1614 views/solutions/statistics.php:68
+#: controllers/solutions.php:1542 views/solutions/statistics.php:68
 #, php-format
 msgid "Item %d"
 msgstr "Item %d"
 
-#: controllers/solutions.php:1627
+#: controllers/solutions.php:1555
 msgid "Statistik.csv"
 msgstr "statistics.csv"
 
-#: controllers/solutions.php:1630
+#: controllers/solutions.php:1558
 msgid ""
 "Diese Seite gibt einen Überblick über die im Durchschnitt von allen "
 "Teilnehmern erreichten Punkte sowie den Prozentsatz der vollständig "
@@ -1292,6 +1287,11 @@ msgstr "Text (multiple lines)"
 msgid "Die hochgeladene Datei \"%s\" ist leer."
 msgstr "The uploaded file \"%s\" is empty."
 
+#: exercises/tb_exercise.php:200 exercises/tb_exercise.php:233
+#: lib/vips_common.inc.php:490
+msgid "Sie haben keinen Zugriff auf diese Datei!"
+msgstr "You don't have access to this file!"
+
 #: lib/CharacterPicker.php:29
 msgid "IPA-Zeichen"
 msgstr "IPA characters"