diff --git a/store/src/java-test/com/zimbra/cs/service/FileUploadServletTest.java b/store/src/java-test/com/zimbra/cs/service/FileUploadServletTest.java
index cf7a0100fd..42e9b8b6a9 100644
--- a/store/src/java-test/com/zimbra/cs/service/FileUploadServletTest.java
+++ b/store/src/java-test/com/zimbra/cs/service/FileUploadServletTest.java
@@ -16,8 +16,6 @@
  */
 package com.zimbra.cs.service;
 
-import static org.junit.Assert.assertTrue;
-
 import java.net.URL;
 import java.util.HashMap;
 import java.util.List;
@@ -27,6 +25,7 @@
 
 import javax.servlet.http.Cookie;
 
+import org.apache.tika.mime.MediaType;
 import org.junit.After;
 import org.junit.Assert;
 import org.junit.Before;
@@ -52,6 +51,12 @@
 import com.zimbra.cs.servlet.CsrfFilter;
 import com.zimbra.soap.SoapServlet;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+
 public class FileUploadServletTest {
     private static FileUploadServlet servlet;
     private static Account testAccount;
@@ -374,4 +379,75 @@ public void testFileUploadAuthTokenCsrfEnabled2() throws Exception {
         String respStrg = resp.output.toString();
         assertTrue(respStrg.contains("200"));
     }
+
+    @Test
+    public void testMediaTypeIsPlainNullOrEmpty() {
+        assertTrue(FileUploadServlet.Upload.mediaTypeIsPlainNullOrEmpty(null));
+        assertTrue(FileUploadServlet.Upload.mediaTypeIsPlainNullOrEmpty(""));
+        assertTrue(FileUploadServlet.Upload.mediaTypeIsPlainNullOrEmpty(" "));
+        assertTrue(FileUploadServlet.Upload.mediaTypeIsPlainNullOrEmpty("text/plain"));
+        assertFalse(FileUploadServlet.Upload.mediaTypeIsPlainNullOrEmpty("application/json"));
+        assertFalse(FileUploadServlet.Upload.mediaTypeIsPlainNullOrEmpty("text/xml"));
+    }
+
+    @Test
+    public void testIsContentTypeXML() {
+        assertFalse(FileUploadServlet.Upload.isContentTypeXML(null));
+        assertFalse(FileUploadServlet.Upload.isContentTypeXML(""));
+        assertFalse(FileUploadServlet.Upload.isContentTypeXML(" "));
+        assertTrue(FileUploadServlet.Upload.isContentTypeXML("text/xml"));
+        assertTrue(FileUploadServlet.Upload.isContentTypeXML("application/xml"));
+        assertFalse(FileUploadServlet.Upload.isContentTypeXML("application/json"));
+        assertFalse(FileUploadServlet.Upload.isContentTypeXML("text/plain"));
+    }
+
+    @Test
+    public void testForSpecialCase_text_xml() {
+        Object[][] scenarios = {
+                // {initialMediaType, contentType, expectedMediaType}
+                // case 1
+                   {"text/plain", "text/xml", "text/xml"},
+                // case 2
+                   {"text/plain", "application/json", null},
+                // case 3
+                   {"application/json", "text/xml", null},
+                // case 4
+                   {"application/json", "application/json", null},
+                // case 5
+                   {null,"text/xml","text/xml"},
+                // case 6
+                   {"","text/xml","text/xml"},
+                // case 7
+                   {"text/plain", null, null},
+                // case 8
+                  {"application/json", null, null}
+        };
+
+        for (Object[] scenario : scenarios) {
+            String initialMediaType = (String) scenario[0];
+            String contentType = (String) scenario[1];
+            String expectedMediaType = (String) scenario[2];
+            MediaType mediaType = null;
+
+            // Actual logic under test
+            if (FileUploadServlet.Upload.mediaTypeIsPlainNullOrEmpty(initialMediaType) &&
+                    FileUploadServlet.Upload.isContentTypeXML(contentType)) {
+                mediaType = MediaType.parse(contentType);
+            }
+
+            // Assertions
+            if (expectedMediaType == null) {
+                assertNull("Failed for scenario: " + scenarioToString(scenario), mediaType);
+            } else {
+                assertNotNull("Failed for scenario: " + scenarioToString(scenario), mediaType);
+                assertEquals("Failed for scenario: " + scenarioToString(scenario), expectedMediaType, mediaType.toString());
+            }
+        }
+    }
+
+    // Helper method to format scenario data for debugging
+    private String scenarioToString(Object[] scenario) {
+        return String.format("initialMediaType='%s', contentType='%s', expectedMediaType='%s'",
+                scenario[0], scenario[1], scenario[2]);
+    }
 }
diff --git a/store/src/java/com/zimbra/cs/service/FileUploadServlet.java b/store/src/java/com/zimbra/cs/service/FileUploadServlet.java
index 510447ce00..a9912581d1 100644
--- a/store/src/java/com/zimbra/cs/service/FileUploadServlet.java
+++ b/store/src/java/com/zimbra/cs/service/FileUploadServlet.java
@@ -214,6 +214,7 @@ public static MimeType getMimeType(FileItem fileItem) {
             metadata.add(Metadata.RESOURCE_NAME_KEY, fileItem.getName());
             String customMimeTypesPath = LC.custom_mimetypes.value();
             MediaType mediaType = null;
+            String contentType = fileItem.getContentType();
             try {
                 TikaInputStream stream = TikaInputStream.get(fileItem.getInputStream());
                 if (new File(customMimeTypesPath).isFile()) {
@@ -222,6 +223,10 @@ public static MimeType getMimeType(FileItem fileItem) {
                 } else {
                     mediaType = detector.detect(stream, metadata);
                 }
+                // special-case text/xml to avoid detection of text/plain
+                if (mediaTypeIsPlainNullOrEmpty(String.valueOf(mediaType)) && isContentTypeXML(contentType)) {
+                    mediaType = MediaType.parse(contentType);
+                }
                 mimeType = tikaConfig.getMimeRepository().forName(mediaType.toString());
                 mLog.debug("Content type detected by tika: %s.", mimeType.toString());
             } catch (MimeTypeException mexp) {
@@ -232,6 +237,16 @@ public static MimeType getMimeType(FileItem fileItem) {
             return mimeType;
         }
 
+        public static boolean mediaTypeIsPlainNullOrEmpty(String mediaType) {
+            return StringUtils.isBlank(mediaType) || MimeConstants.CT_TEXT_PLAIN.equals(mediaType);
+        }
+
+        public static boolean isContentTypeXML(String contentType) {
+            return !StringUtil.isNullOrEmpty(contentType) &&
+                    (MimeConstants.CT_TEXT_XML.equals(contentType) ||
+                            MimeConstants.CT_TEXT_XML_LEGACY.equals(contentType));
+        }
+
         public static String getExtension(MimeType mimeType) {
             String fileExtension = null;
             fileExtension = mimeType == null ? "" : StringUtils.strip(mimeType.getExtension(), ".");