diff --git a/core/src/main/kotlin/org/evomaster/core/output/MongoWriter.kt b/core/src/main/kotlin/org/evomaster/core/output/MongoWriter.kt
index 901d4444bf..084e266f9f 100644
--- a/core/src/main/kotlin/org/evomaster/core/output/MongoWriter.kt
+++ b/core/src/main/kotlin/org/evomaster/core/output/MongoWriter.kt
@@ -58,8 +58,9 @@ object MongoWriter {
                         .forEach { g ->
                             when (g) {
                                 is ObjectGene -> {
-                                    val printableValue =
-                                        StringEscapeUtils.escapeJava(g.getValueAsPrintableString(mode = GeneUtils.EscapeMode.EJSON))
+                                    val ejson = g.getValueAsPrintableString(mode = GeneUtils.EscapeMode.EJSON)
+                                    val printableValue = if (format.isJava()) escapeEjsonForJavaLiteral(ejson)
+                                    else StringEscapeUtils.escapeJava(ejson)
                                     val adaptedPrintableValue = if (format.isKotlin())
                                         printableValue.replace(
                                             "$",
@@ -95,4 +96,19 @@ object MongoWriter {
 
     }
 
+    /**
+     * Escapes EJSON for a Java string literal without leaving a raw backslash-u
+     * sequence. Java translates Unicode escapes before parsing string literals,
+     * so an EJSON value containing a literal backslash followed by 'u' can make
+     * otherwise valid generated tests fail to compile.
+     */
+    internal fun escapeEjsonForJavaLiteral(value: String): String {
+        return StringEscapeUtils.escapeJava(value).replace(ESCAPED_BACKSLASH_U) { match ->
+            val slashCount = match.value.length - 1
+            "\\134".repeat(slashCount / 2) + "u"
+        }
+    }
+
+    private val ESCAPED_BACKSLASH_U = Regex("""(\\\\)+u""")
+
 }
diff --git a/core/src/main/kotlin/org/evomaster/core/problem/rest/data/RestPath.kt b/core/src/main/kotlin/org/evomaster/core/problem/rest/data/RestPath.kt
index 4e1439b4e6..2836c9eaea 100644
--- a/core/src/main/kotlin/org/evomaster/core/problem/rest/data/RestPath.kt
+++ b/core/src/main/kotlin/org/evomaster/core/problem/rest/data/RestPath.kt
@@ -354,7 +354,15 @@ class RestPath(path: String) {
         val data = dynamicResolutionOnlyPathData(params, mapOf())
         assert(data.size == 1)
         assert(!data[0].second)
-        return data[0].first
+        return data[0].first.map { c ->
+        // The URI calls in dynamicResolutionOnlyPathData do not encode non-ASCII characters in path segments.
+            if (c.code > 127) {
+                // non-ASCII
+                encode(c.toString())
+            } else {
+                c.toString()
+            }
+        }.joinToString( "")
     }
 
 
@@ -413,7 +421,7 @@ class RestPath(path: String) {
                             why not using URI also for Query part???
                             it seems unclear how to properly build it as a single string...
                          */
-                        val entry = URI(null, null, path.toString(), null, null).toASCIIString()
+                        val entry = URI(null, null, path.toString(), null, null).rawPath
                         data.add(Pair(entry, false))
                         path.setLength(0) // clear it
                         data.add(Pair(variable, true))
@@ -446,7 +454,7 @@ class RestPath(path: String) {
         }
 
         if(path.isNotEmpty()){
-            val entry = URI(null, null, path.toString(), null, null).toASCIIString()
+            val entry = URI(null, null, path.toString(), null, null).rawPath
             data.add(Pair(entry, false))
         }
 
diff --git a/core/src/main/kotlin/org/evomaster/core/search/service/monitor/SearchProcessMonitor.kt b/core/src/main/kotlin/org/evomaster/core/search/service/monitor/SearchProcessMonitor.kt
index f006895183..224d325945 100644
--- a/core/src/main/kotlin/org/evomaster/core/search/service/monitor/SearchProcessMonitor.kt
+++ b/core/src/main/kotlin/org/evomaster/core/search/service/monitor/SearchProcessMonitor.kt
@@ -109,8 +109,8 @@ class SearchProcessMonitor: SearchListener {
 
     @PostConstruct
     fun postConstruct(){
-        initMonitorProcessOutputs()
         if(config.enableProcessMonitor){
+            initMonitorProcessOutputs()
             time.addListener(this)
             if (config.processFormat == EMConfig.ProcessDataFormat.TEST_IND || config.processFormat == EMConfig.ProcessDataFormat.TARGET_TEST_IND){
                 val dto = try {
diff --git a/core/src/test/kotlin/org/evomaster/core/output/MongoWriterTest.kt b/core/src/test/kotlin/org/evomaster/core/output/MongoWriterTest.kt
new file mode 100644
index 0000000000..66d5a941a2
--- /dev/null
+++ b/core/src/test/kotlin/org/evomaster/core/output/MongoWriterTest.kt
@@ -0,0 +1,18 @@
+package org.evomaster.core.output
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Assertions.assertFalse
+import org.junit.jupiter.api.Test
+
+class MongoWriterTest {
+
+    @Test
+    fun `should escape literal backslash u in EJSON without changing its runtime value`() {
+        val ejson = """{"field":"El24e\\uJTQGh"}"""
+
+        val escaped = MongoWriter.escapeEjsonForJavaLiteral(ejson)
+
+        assertEquals("""{\"field\":\"El24e\134\134uJTQGh\"}""", escaped)
+        assertFalse(Regex("""(\\\\)+u""").containsMatchIn(escaped))
+    }
+}
diff --git a/core/src/test/kotlin/org/evomaster/core/search/service/ProcessMonitorTest.kt b/core/src/test/kotlin/org/evomaster/core/search/service/ProcessMonitorTest.kt
index ad0d393627..4cfedf6397 100644
--- a/core/src/test/kotlin/org/evomaster/core/search/service/ProcessMonitorTest.kt
+++ b/core/src/test/kotlin/org/evomaster/core/search/service/ProcessMonitorTest.kt
@@ -72,25 +72,34 @@ class ProcessMonitorTest{
 
     @Test
     fun testDisableProcessMonitor(){
+        val output = Files.createTempDirectory("process-monitor-disabled-")
+        val marker = output.resolve("marker")
+        Files.createFile(marker)
 
-        config.enableProcessMonitor = false
-        config.showProgress = true
+        try {
+            config.processFiles = output.toString()
+            config.enableProcessMonitor = false
+            config.showProgress = true
 
-        processMonitor.postConstruct()
-        assertFalse(Files.exists(Paths.get(config.processFiles)))
+            processMonitor.postConstruct()
+            assertTrue(Files.exists(marker))
 
-        val a = OneMaxIndividual(2)
-        TestUtils.doInitializeIndividualForTesting(a,randomness)
-        a.setValue(0, 1.0)
+            val a = OneMaxIndividual(2)
+            TestUtils.doInitializeIndividualForTesting(a,randomness)
+            a.setValue(0, 1.0)
 
-        val eval = ff.calculateCoverage(a, modifiedSpec = null)!!
-        processMonitor.eval = eval
-        processMonitor.newActionsEvaluated(1)
+            val eval = ff.calculateCoverage(a, modifiedSpec = null)!!
+            processMonitor.eval = eval
+            processMonitor.newActionsEvaluated(1)
 
-        val added = archive.addIfNeeded(eval)
-        processMonitor.record(added, true, eval)
+            val added = archive.addIfNeeded(eval)
+            processMonitor.record(added, true, eval)
 
-        assertFalse(Files.exists(Paths.get(config.processFiles)))
+            assertTrue(Files.exists(marker))
+        } finally {
+            Files.deleteIfExists(marker)
+            Files.deleteIfExists(output)
+        }
     }
 
     @Test