diff --git a/seminar/views/views_all.py b/seminar/views/views_all.py
index 318eee21..662c5025 100644
--- a/seminar/views/views_all.py
+++ b/seminar/views/views_all.py
@@ -8,6 +8,7 @@ from django.http import Http404
 from django.db.models import Q, Sum, Count
 from django.views.generic.base import RedirectView
 from django.core.exceptions import PermissionDenied
+from django.contrib.staticfiles.finders import find
 
 import seminar.models as s
 import seminar.models as m
@@ -36,6 +37,7 @@ import unicodedata
 import logging
 import time
 from collections.abc import Sequence
+import http
 
 from seminar.utils import aktivniResitele
 
@@ -562,17 +564,25 @@ def cisloObalkyView(request, rocnik, cislo):
 
 
 def obalkyView(request, resitele):
+	if len(resitele) == 0:
+		return HttpResponse(
+			render(request, 'universal.html', {
+				'title': 'Není pro koho vyrobit obálky.',
+				'text': 'Právě ses pokusil/a vygenerovat obálky pro prázdnou množinu lidí. Můžeš to zkusit změnit, případně se zeptej webařů :-)',
+				}),
+			status=http.HTTPStatus.NOT_FOUND,
+			)
+
 	tex = render(request,'seminar/archiv/obalky.tex', {'resitele': resitele}).content
 
-	tempdir = tempfile.mkdtemp()
-	with open(tempdir+"/obalky.tex","w") as texfile:
-		texfile.write(tex.decode())
-	shutil.copy(os.path.join(settings.STATIC_ROOT, 'seminar/lisak.pdf'), tempdir)
-	subprocess.call(["pdflatex","obalky.tex"], cwd = tempdir)
+	with tempfile.TemporaryDirectory() as tempdir:
+		with open(tempdir+"/obalky.tex","w") as texfile:
+			texfile.write(tex.decode())
+		shutil.copy(find('seminar/lisak.pdf'), tempdir)
+		subprocess.call(["pdflatex","obalky.tex"], cwd = tempdir)
 
-	with open(tempdir+"/obalky.pdf","rb") as pdffile:
-		response = HttpResponse(pdffile.read(), content_type='application/pdf')
-	shutil.rmtree(tempdir)
+		with open(tempdir+"/obalky.pdf","rb") as pdffile:
+			response = HttpResponse(pdffile.read(), content_type='application/pdf')
 	return response
 
 
diff --git a/soustredeni/views.py b/soustredeni/views.py
index f2aafdf7..f150b6b8 100644
--- a/soustredeni/views.py
+++ b/soustredeni/views.py
@@ -9,6 +9,7 @@ import tempfile
 import shutil
 import subprocess
 from pathlib import Path
+import http
 
 from seminar.views import obalkyView
 
@@ -76,17 +77,25 @@ def soustredeniUcastniciExportView(request, soustredeni):
 def soustredeniStvrzenkyView(request, soustredeni):
 	soustredeni = get_object_or_404(Soustredeni, id=soustredeni)
 	ucastnici = Resitel.objects.filter(soustredeni=soustredeni)
+	if ucastnici.count() == 0:
+		return HttpResponse(
+			render(request, 'universal.html', {
+				'title': 'Není pro koho vyrobit stvrzenky.',
+				'text': 'Právě ses pokusil/a vygenerovat stvrzenky pro prázdnou množinu lidí. Můžeš to zkusit změnit, případně se zeptej webařů :-)',
+				}),
+			status=http.HTTPStatus.NOT_FOUND,
+			)
 	castka = Nastaveni.get_solo().cena_sous
 	tex = render(request, 'soustredeni/stvrzenky.tex', {'ucastnici': ucastnici, 'soustredeni': soustredeni, 'castka': castka}).content
 
-	tempdir = Path(tempfile.mkdtemp())
-	with open(tempdir / "stvrzenky.tex", "w") as texfile:
-		texfile.write(tex.decode())
+	with tempfile.TemporaryDirectory() as tempdirfn:
+		tempdir = Path(tempdirfn)
+		with open(tempdir / "stvrzenky.tex", "w") as texfile:
+			texfile.write(tex.decode())
 
-	shutil.copy(find('images/logomm.pdf'), tempdir)
-	subprocess.call(["pdflatex", "stvrzenky.tex"], cwd = tempdir, stdout=subprocess.DEVNULL)
+		shutil.copy(find('images/logomm.pdf'), tempdir)
+		subprocess.call(["pdflatex", "stvrzenky.tex"], cwd = tempdir, stdout=subprocess.DEVNULL)
 
-	with open(tempdir / "stvrzenky.pdf", "rb") as pdffile:
-		response = HttpResponse(pdffile.read(), content_type='application/pdf')
-	shutil.rmtree(tempdir)
+		with open(tempdir / "stvrzenky.pdf", "rb") as pdffile:
+			response = HttpResponse(pdffile.read(), content_type='application/pdf')
 	return response