diff --git a/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/rest/TbHttpClient.java b/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/rest/TbHttpClient.java
index 0d5a78810b..e9476157aa 100644
--- a/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/rest/TbHttpClient.java
+++ b/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/rest/TbHttpClient.java
@@ -217,7 +217,7 @@ public class TbHttpClient {
             String endpointUrl = TbNodeUtils.processPattern(config.getRestEndpointUrlPattern(), msg);
 
             List<QueryParam> processedQueryParams;
-            if (config.isUseNewEncoding()) {
+            if (config.getQueryParams() != null) {
                 processedQueryParams = config.getQueryParams().stream()
                         .map(param -> {
                             var processedParamName = TbNodeUtils.processPattern(param.name(), msg);
@@ -312,9 +312,9 @@ public class TbHttpClient {
             queryParams.forEach(param -> builder.addParameter(param.name(), param.value()));
             return builder.build();
         } catch (URISyntaxException e) {
-            throw new IllegalArgumentException("""
-                    Invalid request URL: '%s'. The URL must be valid and properly encoded.
-                    If URL contains special characters (e.g., spaces), they must be percent-encoded (e.g., '/my file/' should be '/my%%20file/').""".formatted(endpointUrl), e);
+            throw new IllegalArgumentException(
+                    "Invalid request URL: '" + endpointUrl + "'. The URL must be valid and properly encoded. " +
+                            "If URL contains special characters (e.g., spaces), they must be percent-encoded (e.g., '/my device/' should be '/my%20device/').", e);
         }
     }
 
@@ -327,10 +327,10 @@ public class TbHttpClient {
      * Pre-encoding the URL (e.g., {@code email=user%2Btag@test.com}) doesn't help
      * because {@code .encode()} will double-encode it to {@code email=user%252Btag@test.com}.
      * <p>
-     * Use {@link #buildEncodedUriNew} with a separate query params map,
+     * Use {@link #buildEncodedUriNew} with a separate query params list,
      * where values are encoded exactly once: {@code +} → {@code %2B}, {@code @} → {@code %40}.
      */
-    @Deprecated(since = "4.2.1.2", forRemoval = true) // fixme: remove in major 5.0
+    @Deprecated(since = "4.2.1.2", forRemoval = true)
     private URI buildEncodedUriLegacy(String endpointUrl) {
         return UriComponentsBuilder.fromUriString(endpointUrl).build().encode().toUri();
     }
diff --git a/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/rest/TbRestApiCallNodeConfiguration.java b/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/rest/TbRestApiCallNodeConfiguration.java
index cd12eb5211..d319d15157 100644
--- a/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/rest/TbRestApiCallNodeConfiguration.java
+++ b/rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/rest/TbRestApiCallNodeConfiguration.java
@@ -15,10 +15,8 @@
  */
 package org.thingsboard.rule.engine.rest;
 
-import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import jakarta.validation.Valid;
-import jakarta.validation.constraints.AssertTrue;
 import jakarta.validation.constraints.NotNull;
 import lombok.Data;
 import org.springframework.http.HttpHeaders;
@@ -37,7 +35,6 @@ public class TbRestApiCallNodeConfiguration implements NodeConfiguration<TbRestA
 
     private String restEndpointUrlPattern;
     private String requestMethod;
-    private boolean useNewEncoding;
     private List<@NotNull @Valid QueryParam> queryParams;
     private Map<String, String> headers;
     private boolean useSimpleClientHttpFactory;
@@ -55,31 +52,12 @@ public class TbRestApiCallNodeConfiguration implements NodeConfiguration<TbRestA
     private boolean ignoreRequestBody;
     private int maxInMemoryBufferSizeInKb;
 
-    @JsonIgnore
-    @AssertTrue(message = "query parameters must be non-null if new encoding is used")
-    public boolean isNewEncodingConfigValid() {
-        if (useNewEncoding) {
-            return queryParams != null;
-        }
-        return true;
-    }
-
-    @JsonIgnore
-    @AssertTrue(message = "query parameters must be null if old encoding is used")
-    public boolean isLegacyEncodingConfigValid() {
-        if (!useNewEncoding) {
-            return queryParams == null;
-        }
-        return true;
-    }
-
     @Override
     public TbRestApiCallNodeConfiguration defaultConfiguration() {
         TbRestApiCallNodeConfiguration configuration = new TbRestApiCallNodeConfiguration();
         configuration.setRestEndpointUrlPattern("http://localhost/api");
         configuration.setRequestMethod("POST");
         configuration.setHeaders(Collections.singletonMap(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON_VALUE));
-        configuration.setUseNewEncoding(true);
         configuration.setQueryParams(Collections.emptyList());
         configuration.setUseSimpleClientHttpFactory(false);
         configuration.setReadTimeoutMs(0);
diff --git a/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/rest/TbHttpClientTest.java b/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/rest/TbHttpClientTest.java
index 4082aa8163..9d3db7e1d8 100644
--- a/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/rest/TbHttpClientTest.java
+++ b/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/rest/TbHttpClientTest.java
@@ -144,7 +144,6 @@ public class TbHttpClientTest {
             config.setRestEndpointUrlPattern("http://localhost:" + server.getPort() + path);
             config.setRequestMethod("GET");
             config.setUseSimpleClientHttpFactory(true);
-            config.setUseNewEncoding(true);
             config.setQueryParams(List.of(
                     new QueryParam("email", "${userEmail}"),              // ${} from metadata
                     new QueryParam("device", "${deviceName}"),            // ${} from metadata
@@ -192,7 +191,6 @@ public class TbHttpClientTest {
             var config = new TbRestApiCallNodeConfiguration().defaultConfiguration();
             config.setRestEndpointUrlPattern("http://localhost:" + server.getPort() + path + "?data=" + paramValue);
             config.setRequestMethod("GET");
-            config.setUseNewEncoding(false);
             config.setQueryParams(null);
 
             var msg = TbMsg.newMsg()
diff --git a/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/rest/TbRestApiCallNodeTest.java b/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/rest/TbRestApiCallNodeTest.java
index 39d9e0d585..b2d6fac12b 100644
--- a/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/rest/TbRestApiCallNodeTest.java
+++ b/rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/rest/TbRestApiCallNodeTest.java
@@ -51,6 +51,7 @@ import org.thingsboard.server.common.msg.TbMsgMetaData;
 import org.thingsboard.server.dao.exception.DataValidationException;
 
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.CountDownLatch;
@@ -59,7 +60,6 @@ import java.util.stream.Stream;
 
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNotSame;
 import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
@@ -123,7 +123,6 @@ public class TbRestApiCallNodeTest extends AbstractRuleNodeUpgradeTest {
     public void shouldNotAllowNullQueryParamNames() {
         // GIVEN
         var config = new TbRestApiCallNodeConfiguration().defaultConfiguration();
-        config.setUseNewEncoding(true);
         config.setQueryParams(List.of(new QueryParam(null, "value")));
 
         // WHEN-THEN
@@ -139,7 +138,6 @@ public class TbRestApiCallNodeTest extends AbstractRuleNodeUpgradeTest {
     public void shouldNotAllowNullQueryParamValues() {
         // GIVEN
         var config = new TbRestApiCallNodeConfiguration().defaultConfiguration();
-        config.setUseNewEncoding(true);
         config.setQueryParams(List.of(new QueryParam("key", null)));
 
         // WHEN-THEN
@@ -152,33 +150,22 @@ public class TbRestApiCallNodeTest extends AbstractRuleNodeUpgradeTest {
     }
 
     @Test
-    public void shouldAllowOnlyNullQueryParamsIfOldEncodingIsUsed() {
+    public void shouldNotAllowNullQueryParamEntries() {
         // GIVEN
         var config = new TbRestApiCallNodeConfiguration().defaultConfiguration();
-        config.setUseNewEncoding(false);
-        config.setQueryParams(List.of(new QueryParam("key", "value")));
 
-        // WHEN-THEN
-        assertThatThrownBy(() -> new TbRestApiCallNode().init(ctx, new TbNodeConfiguration(JacksonUtil.valueToTree(config))))
-                .isInstanceOf(TbNodeException.class)
-                .hasRootCauseInstanceOf(DataValidationException.class)
-                .hasRootCauseMessage("'" + ruleNode.getName() + "' node configuration is invalid: query parameters must be null if old encoding is used")
-                .matches(e -> ((TbNodeException) e).isUnrecoverable());
-    }
-
-    @Test
-    public void shouldNotAllowNullQueryParamsIfNewEncodingIsUsed() {
-        // GIVEN
-        var config = new TbRestApiCallNodeConfiguration().defaultConfiguration();
-        config.setUseNewEncoding(true);
-        config.setQueryParams(null);
+        var queryParams = new ArrayList<QueryParam>();
+        queryParams.add(new QueryParam("key", "value"));
+        queryParams.add(null);
+        config.setQueryParams(queryParams);
 
         // WHEN-THEN
         assertThatThrownBy(() -> new TbRestApiCallNode().init(ctx, new TbNodeConfiguration(JacksonUtil.valueToTree(config))))
                 .isInstanceOf(TbNodeException.class)
-                .hasRootCauseInstanceOf(DataValidationException.class)
-                .hasRootCauseMessage("'" + ruleNode.getName() + "' node configuration is invalid: query parameters must be non-null if new encoding is used")
-                .matches(e -> ((TbNodeException) e).isUnrecoverable());
+                .matches(e -> ((TbNodeException) e).isUnrecoverable())
+                .rootCause()
+                .isInstanceOf(DataValidationException.class)
+                .hasMessageContaining("must not be null");
     }
 
     @Test
@@ -187,7 +174,6 @@ public class TbRestApiCallNodeTest extends AbstractRuleNodeUpgradeTest {
         var defaultConfig = new TbRestApiCallNodeConfiguration().defaultConfiguration();
 
         // THEN
-        assertTrue(defaultConfig.isUseNewEncoding());
         assertEquals(Collections.emptyList(), defaultConfig.getQueryParams());
     }
 
@@ -224,7 +210,6 @@ public class TbRestApiCallNodeTest extends AbstractRuleNodeUpgradeTest {
         var config = JacksonUtil.fromString(configJson, TbRestApiCallNodeConfiguration.class);
 
         // THEN
-        assertFalse(config.isUseNewEncoding());
         assertNull(config.getQueryParams());
     }