diff --git a/Backend.hs b/Backend.hs
--- a/Backend.hs
+++ b/Backend.hs
@@ -94,7 +94,7 @@
 lookupBackendVariety :: KeyVariety -> Backend
 lookupBackendVariety v = fromMaybe unknown $ maybeLookupBackendVariety v
   where
-	unknown = error $ "unknown backend " ++ formatKeyVariety v
+	unknown = giveup $ "unknown backend " ++ formatKeyVariety v
 
 maybeLookupBackendVariety :: KeyVariety -> Maybe Backend
 maybeLookupBackendVariety v = M.lookup v varietyMap
diff --git a/CHANGELOG b/CHANGELOG
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,10 @@
+git-annex (6.20170301.1) unstable; urgency=medium
+
+  * Fix reversion in yesterday's release that made SHA1E and MD5E backends
+    not work.
+
+ -- Joey Hess <id@joeyh.name>  Wed, 01 Mar 2017 12:46:03 -0400
+
 git-annex (6.20170301) unstable; urgency=medium
 
   * No changes from 6.20170228; a new version number was needed due
diff --git a/Types/Key.hs b/Types/Key.hs
--- a/Types/Key.hs
+++ b/Types/Key.hs
@@ -89,7 +89,7 @@
 	addsz (HashSize n) s =  s ++ show n
 
 parseKeyVariety :: String -> KeyVariety
-parseKeyVariety "SHA256"    =  SHA2Key (HashSize 256) (HasExt False)
+parseKeyVariety "SHA256"    = SHA2Key (HashSize 256) (HasExt False)
 parseKeyVariety "SHA256E"   = SHA2Key (HashSize 256) (HasExt True)
 parseKeyVariety "SHA512"    = SHA2Key (HashSize 512) (HasExt False)
 parseKeyVariety "SHA512E"   = SHA2Key (HashSize 512) (HasExt True)
@@ -110,7 +110,9 @@
 parseKeyVariety "SKEIN256"  = SKEINKey (HashSize 256) (HasExt False)
 parseKeyVariety "SKEIN256E" = SKEINKey (HashSize 256) (HasExt True)
 parseKeyVariety "SHA1"      = SHA1Key (HasExt False)
+parseKeyVariety "SHA1E"     = SHA1Key (HasExt True)
 parseKeyVariety "MD5"       = MD5Key (HasExt False)
+parseKeyVariety "MD5E"      = MD5Key (HasExt True)
 parseKeyVariety "WORM"      = WORMKey
 parseKeyVariety "URL"       = URLKey
 parseKeyVariety s           = OtherKey s
diff --git a/git-annex.cabal b/git-annex.cabal
--- a/git-annex.cabal
+++ b/git-annex.cabal
@@ -1,5 +1,5 @@
 Name: git-annex
-Version: 6.20170301
+Version: 6.20170301.1
 Cabal-Version: >= 1.8
 License: GPL-3
 Maintainer: Joey Hess <id@joeyh.name>