diff --git a/go.sum b/go.sum
index d7444cc7..d04e8195 100644
--- a/go.sum
+++ b/go.sum
@@ -1,5 +1,4 @@
 cloud.google.com/go v0.34.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
-github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.4.0-rc.1/go.mod h1:ceaxUfeHdC40wWswd/P6IGgMaK3YpKi5j83Wpe3EHw8=
@@ -36,7 +35,6 @@ golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-google.golang.org/appengine v1.4.0 h1:/wp5JvzpHIxhs/dumFmF7BXTf3Z+dd4uXta4kVyO508=
 google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 google.golang.org/appengine v1.6.7 h1:FZR1q0exgwxzPzp/aF+VccGrSfxfPpkBqjIIEq3ru6c=
 google.golang.org/appengine v1.6.7/go.mod h1:8WjMMxjGQR8xUklV/ARdw2HLXBOI7O7uCIDZVag1xfc=
diff --git a/odata/odata.go b/odata/odata.go
index 9cd15b62..07152cc2 100644
--- a/odata/odata.go
+++ b/odata/odata.go
@@ -83,18 +83,17 @@ func (e *Error) UnmarshalJSON(data []byte) error {
 	*e = Error(e2)
 
 	// Unmarshal the message, which can be a plain string or an object wrapping a message
-	if e.RawMessage != nil {
-		raw := *e.RawMessage
-		switch string(raw[0]) {
+	if raw := e.RawMessage; raw != nil && len(*raw) > 0 {
+		switch string((*raw)[0]) {
 		case "\"":
 			var s string
-			if err := json.Unmarshal(raw, &s); err != nil {
+			if err := json.Unmarshal(*raw, &s); err != nil {
 				return err
 			}
 			e.Message = &s
 		case "{":
 			var m map[string]interface{}
-			if err := json.Unmarshal(raw, &m); err != nil {
+			if err := json.Unmarshal(*raw, &m); err != nil {
 				return err
 			}
 			if v, ok := m["value"]; ok {
@@ -103,7 +102,7 @@ func (e *Error) UnmarshalJSON(data []byte) error {
 				}
 			}
 		default:
-			return fmt.Errorf("unrecognised error message: %#v", string(raw))
+			return fmt.Errorf("unrecognised error message: %#v", string(*raw))
 		}
 	}
 	return nil