diff --git a/DeDRM_Macintosh_Application/DeDRM.app/Contents/Resources/ion.py b/DeDRM_Macintosh_Application/DeDRM.app/Contents/Resources/ion.py
index c100191..40433ca 100644
--- a/DeDRM_Macintosh_Application/DeDRM.app/Contents/Resources/ion.py
+++ b/DeDRM_Macintosh_Application/DeDRM.app/Contents/Resources/ion.py
@@ -23,13 +23,17 @@ from Crypto.Util.py3compat import bchr, bord
 try:
     # lzma library from calibre 2.35.0 or later
     import lzma.lzma1 as calibre_lzma
-except:
+except ImportError:
     calibre_lzma = None
     try:
         import lzma
-    except:
+    except ImportError:
         # Need pip backports.lzma on Python <3.3
-        from backports import lzma
+        try:
+            from backports import lzma
+        except ImportError:
+            # Windows-friendly choice: pylzma wheels
+            import pylzma as lzma
 
 
 TID_NULL = 0
diff --git a/DeDRM_Macintosh_Application/DeDRM.app/Contents/Resources/kfxdedrm.py b/DeDRM_Macintosh_Application/DeDRM.app/Contents/Resources/kfxdedrm.py
index 8885e09..c2b9bb1 100644
--- a/DeDRM_Macintosh_Application/DeDRM.app/Contents/Resources/kfxdedrm.py
+++ b/DeDRM_Macintosh_Application/DeDRM.app/Contents/Resources/kfxdedrm.py
@@ -15,9 +15,9 @@ except ImportError:
     from StringIO import StringIO
 
 try:
-    import ion
-except:
     from calibre_plugins.dedrm import ion
+except ImportError:
+    import ion
 
 
 __license__ = 'GPL v3'
diff --git a/DeDRM_Windows_Application/DeDRM_App/DeDRM_lib/lib/ion.py b/DeDRM_Windows_Application/DeDRM_App/DeDRM_lib/lib/ion.py
index c100191..40433ca 100644
--- a/DeDRM_Windows_Application/DeDRM_App/DeDRM_lib/lib/ion.py
+++ b/DeDRM_Windows_Application/DeDRM_App/DeDRM_lib/lib/ion.py
@@ -23,13 +23,17 @@ from Crypto.Util.py3compat import bchr, bord
 try:
     # lzma library from calibre 2.35.0 or later
     import lzma.lzma1 as calibre_lzma
-except:
+except ImportError:
     calibre_lzma = None
     try:
         import lzma
-    except:
+    except ImportError:
         # Need pip backports.lzma on Python <3.3
-        from backports import lzma
+        try:
+            from backports import lzma
+        except ImportError:
+            # Windows-friendly choice: pylzma wheels
+            import pylzma as lzma
 
 
 TID_NULL = 0
diff --git a/DeDRM_Windows_Application/DeDRM_App/DeDRM_lib/lib/kfxdedrm.py b/DeDRM_Windows_Application/DeDRM_App/DeDRM_lib/lib/kfxdedrm.py
index 8885e09..c2b9bb1 100644
--- a/DeDRM_Windows_Application/DeDRM_App/DeDRM_lib/lib/kfxdedrm.py
+++ b/DeDRM_Windows_Application/DeDRM_App/DeDRM_lib/lib/kfxdedrm.py
@@ -15,9 +15,9 @@ except ImportError:
     from StringIO import StringIO
 
 try:
-    import ion
-except:
     from calibre_plugins.dedrm import ion
+except ImportError:
+    import ion
 
 
 __license__ = 'GPL v3'