diff --git a/cups-genppdupdate.py.in b/cups-genppdupdate.py.in
index d65e618..ef4b879 100755
--- a/cups-genppdupdate.py.in
+++ b/cups-genppdupdate.py.in
@@ -255,6 +255,23 @@ def parse_options():
 
     return args
 
+def check_encoding(filename):
+    import chardet
+
+    with open(filename, 'rb') as f:
+         charenc = chardet.detect(f.read())['encoding']
+
+    if debug & 1:
+        print("File encoding: {}".format(charenc))
+
+    if charenc in ['ascii', 'utf-8']:
+        return 'utf-8'
+    else:
+        if debug & 1:
+            print("Trying to use latin1 for decoding {}".format(charenc))
+
+        return 'latin1'
+
 def update_ppd (ppd_source_filename):
     global ppd_dest_filename
     global ppd_out_dir
@@ -271,7 +288,8 @@ def update_ppd (ppd_source_filename):
         ppd_dest_filename = "%s/%s" % (ppd_out_dir,
                                        os.path.basename (ppd_dest_filename))
 
-    orig = open (ppd_source_filename, encoding="utf-8")
+    fenc = check_encoding(ppd_source_filename)
+    orig = open(ppd_source_filename, encoding=fenc)
     orig_metadata = os.fstat (orig.fileno ())
     if debug & 1:
         print ("Source Filename: %s" % ppd_source_filename)
@@ -284,7 +302,17 @@ def update_ppd (ppd_source_filename):
     region = ""
     valid = 0
     orig_locale = ""
-    for line in orig.readlines ():
+
+    try:
+        orig_lines = orig.readlines()
+    except UnicodeDecodeError:
+        if debug & 1:
+            print('PPD {} has an unexpected enconding, '
+                  'skipping.'.format(ppd_source_filename))
+
+        return -1
+
+    for line in orig_lines:
         line.rstrip ()
         if line.find ("*StpLocale:") != -1:
             match = re.search ("\*StpLocale:\s*\"(.*)\"$", line)
diff --git a/gutenprint-python36syntax.patch b/gutenprint-python36syntax.patch
index 5b28195..cd7e258 100644
--- a/gutenprint-python36syntax.patch
+++ b/gutenprint-python36syntax.patch
@@ -1,7 +1,7 @@
 --- gutenprint-5.2.12/src/cups/cups-genppdupdate.in.python36syntax	
 +++ gutenprint-5.2.12/src/cups/cups-genppdupdate.in	
 @@ -287,7 +287,7 @@ def update_ppd (ppd_source_filename):
-     for line in orig.readlines ():
+     for line in orig_lines:
          line.rstrip ()
          if line.find ("*StpLocale:") != -1:
 -            match = re.search ("\*StpLocale:\s*\"(.*)\"$", line)
diff --git a/gutenprint.spec b/gutenprint.spec
index ae2aca0..011bfee 100644
--- a/gutenprint.spec
+++ b/gutenprint.spec
@@ -4,7 +4,7 @@
 Name:           gutenprint
 Summary:        Printer Drivers Package
 Version:        5.3.3
-Release:        6%{?dist}
+Release:        7%{?dist}
 URL:            http://gimp-print.sourceforge.net/
 Source0:        http://downloads.sourceforge.net/gimp-print/%{name}-%{version}.tar.xz
 # Post-install script to update CUPS native PPDs.
@@ -244,6 +244,9 @@ exit 0
 %{_mandir}/man8/cups-genppd*8*.gz
 
 %changelog
+* Fri Nov 06 2020 Zdenek Dohnal <zdohnal@redhat.com> - 5.3.3-7
+- 1773690 - cups-genppdupdate doesnt work for non-utf-8 PPDs
+
 * Thu Nov 05 2020 Zdenek Dohnal <zdohnal@redhat.com> - 5.3.3-6
 - make is no longer in buildroot by default