diff --git a/src/org/opendatakit/briefcase/model/form/FormMetadata.java b/src/org/opendatakit/briefcase/model/form/FormMetadata.java
index 51fca1000..d67be0324 100644
--- a/src/org/opendatakit/briefcase/model/form/FormMetadata.java
+++ b/src/org/opendatakit/briefcase/model/form/FormMetadata.java
@@ -1,6 +1,7 @@
 package org.opendatakit.briefcase.model.form;
 
 import static org.opendatakit.briefcase.model.form.AsJson.getJson;
+import static org.opendatakit.briefcase.util.Host.isWindows;
 
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
@@ -110,9 +111,12 @@ FormMetadata withLastExportedSubmission(String instanceId, OffsetDateTime submis
 
   @Override
   public ObjectNode asJson(ObjectMapper mapper) {
+    String portableFormDir = isWindows()
+        ? formDir.toString().replace("\\", "/")
+        : formDir.toString();
     ObjectNode root = mapper.createObjectNode();
     root.putObject("key").setAll(key.asJson(mapper));
-    root.put("formDir", formDir.toString());
+    root.put("formDir", portableFormDir);
     root.put("hasBeenPulled", hasBeenPulled);
     root.putObject("cursor").setAll(cursor.asJson(mapper));
     lastExportedSubmission.ifPresent(o -> root.putObject("lastExportedSubmission").setAll(o.asJson(mapper)));
diff --git a/test/java/org/opendatakit/aggregate/form/XFormParametersTest.java b/test/java/org/opendatakit/aggregate/form/XFormParametersTest.java
index fe012df68..3410ae356 100644
--- a/test/java/org/opendatakit/aggregate/form/XFormParametersTest.java
+++ b/test/java/org/opendatakit/aggregate/form/XFormParametersTest.java
@@ -87,4 +87,4 @@ public Matcher<XFormParameters> apply(XFormParameters value) {
       return matcherProvider.apply(value);
     }
   }
-}
\ No newline at end of file
+}
diff --git a/test/java/org/opendatakit/briefcase/util/StringUtilsTest.java b/test/java/org/opendatakit/briefcase/util/StringUtilsTest.java
index fcad77566..b111ed1f0 100644
--- a/test/java/org/opendatakit/briefcase/util/StringUtilsTest.java
+++ b/test/java/org/opendatakit/briefcase/util/StringUtilsTest.java
@@ -1,53 +1,40 @@
 package org.opendatakit.briefcase.util;
 
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
-import org.junit.Assert;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.nullValue;
+import static org.junit.Assert.assertThat;
+import static org.opendatakit.briefcase.util.StringUtils.stripIllegalChars;
+
+import java.util.Arrays;
+import java.util.Collection;
 import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
 
+@RunWith(value = Parameterized.class)
 public class StringUtilsTest {
-
-  @Test
-  public void stripIllegalChars_shouldReturnNullForNullInput() {
-    Assert.assertNull(StringUtils.stripIllegalChars(null));
-  }
-
-  @Test
-  public void stripIllegalChars_shouldRemovePunctuationChars() {
-    String input = "abcdef.:;";
-    String output = StringUtils.stripIllegalChars(input);
-
-    Pattern pattern = Pattern.compile("\\p{Punct}");
-    Matcher matcher = pattern.matcher(output);
-    Assert.assertTrue(!matcher.matches());
-    Assert.assertEquals("abcdef___", output);
+  @Parameterized.Parameter(value = 0)
+  public String testCase;
+
+  @Parameterized.Parameter(value = 1)
+  public String input;
+
+  @Parameterized.Parameter(value = 2)
+  public String expectedOutput;
+
+  @Parameterized.Parameters(name = "{0}")
+  public static Collection<Object[]> data() {
+    return Arrays.asList(new Object[][]{
+        {"null input produces null output", null, null},
+        {"Common punctuation chars get replaced by underscore", "abcdef.:;", "abcdef___"},
+        {"Windows and *nix dir separators get replaced by underscore", "a\\b/c", "a_b_c"},
+        {"Whitespace chars get normalized", "abcdef\t\n\r ", "abcdef    "},
+        {"Unicode chars should get through", "シャンプー", "シャンプー"},
+    });
   }
 
   @Test
-  public void stripIllegalChars_shouldReplaceWhitespaceWithSpace() {
-    String input = "abcdef\t\n\r";
-    String output = StringUtils.stripIllegalChars(input);
-
-    Pattern pattern = Pattern.compile("[\\t\\n\\x0B\\f\\r]");
-    Matcher matcher = pattern.matcher(output);
-    Assert.assertTrue(String.format("Input: %s, output: %s", input, output), !matcher.matches());
-    Assert.assertEquals("abcdef   ", output);
+  public void test_stripIllegalChars() {
+    assertThat(stripIllegalChars(input), expectedOutput == null ? is(nullValue()) : is(expectedOutput));
   }
-
-  @Test
-  public void stripIllegalChars_shouldWorkWithUnicodeCharacters() {
-    String input = ".:;%&シャンプー \n\r";
-    String output = StringUtils.stripIllegalChars(input);
-
-    Pattern pattern = Pattern.compile("\\p{Punct}");
-    Matcher matcher = pattern.matcher(output);
-    Assert.assertTrue(String.format("Input: %s, output: %s", input, output), !matcher.matches());
-
-    pattern = Pattern.compile("[\\t\\n\\x0B\\f\\r]");
-    matcher = pattern.matcher(output);
-    Assert.assertTrue(String.format("Input: %s, output: %s", input, output), !matcher.matches());
-
-    Assert.assertEquals("_____シャンプー   ", output);
-  }
-
 }