diff --git a/web/documentserver-example/java/src/main/java/controllers/IndexServlet.java b/web/documentserver-example/java/src/main/java/controllers/IndexServlet.java
index 26206d81..89e01672 100755
--- a/web/documentserver-example/java/src/main/java/controllers/IndexServlet.java
+++ b/web/documentserver-example/java/src/main/java/controllers/IndexServlet.java
@@ -635,7 +635,7 @@ public class IndexServlet extends HttpServlet {
             String newfilename = (String) body.get("newfilename");
             String dockey = (String) body.get("dockey");
 
-            String origExt = "." + (String) body.get("ext");
+            String origExt = (String) body.get("ext");
             String curExt = newfilename;
 
             if (newfilename.indexOf(".") != -1) {
@@ -643,7 +643,7 @@ public class IndexServlet extends HttpServlet {
             }
 
             if (origExt.compareTo(curExt) != 0) {
-                newfilename += origExt;
+                newfilename += "." + origExt;
             }
 
             HashMap<String, String> meta = new HashMap<>();
@@ -724,7 +724,7 @@ public class IndexServlet extends HttpServlet {
             referenceData.put("fileKey", gson.toJson(fileKey));
 
             HashMap<String, Object> data = new HashMap<>();
-            data.put("fileType", FileUtility.getFileExtension(fileName).replace(".", ""));
+            data.put("fileType", FileUtility.getFileExtension(fileName));
             data.put("url", DocumentManager.getDownloadUrl(fileName, true));
             data.put("directUrl", directUrl ? DocumentManager.getDownloadUrl(fileName, false) : null);
             data.put("referenceData", referenceData);
@@ -805,7 +805,7 @@ public class IndexServlet extends HttpServlet {
             bumpedChangesFileWriter.close();
 
             String sourceExtension = FileUtility.getFileExtension(sourceBasename);
-            String previousBasename = "prev" + sourceExtension;
+            String previousBasename = "prev." + sourceExtension;
 
             Path bumpedFile = Paths.get(bumpedVersionStringDirectory, previousBasename);
             Files.move(sourcePathFile, bumpedFile);
@@ -947,16 +947,16 @@ public class IndexServlet extends HttpServlet {
                         key = DocumentManager.readFileToEnd(new File(verDir + File.separator + "key.txt"));
                     }
 
-                    dataObj.put("fileType", FileUtility.getFileExtension(fileName).substring(1));
+                    dataObj.put("fileType", FileUtility.getFileExtension(fileName));
                     dataObj.put("key", key);
                     dataObj.put("url", i == curVer
                             ? DocumentManager.getDownloadUrl(fileName, true)
-                            : DocumentManager.getDownloadHistoryUrl(fileName, i, "prev" + FileUtility
+                            : DocumentManager.getDownloadHistoryUrl(fileName, i, "prev." + FileUtility
                                     .getFileExtension(fileName), true));
                     if (directUrl.equals("true")) {
                         dataObj.put("directUrl", i == curVer
                                 ? DocumentManager.getDownloadUrl(fileName, false)
-                                : DocumentManager.getDownloadHistoryUrl(fileName, i, "prev" + FileUtility
+                                : DocumentManager.getDownloadHistoryUrl(fileName, i, "prev." + FileUtility
                                         .getFileExtension(fileName), false));
                     }
 
diff --git a/web/documentserver-example/java/src/main/java/entities/FileModel.java b/web/documentserver-example/java/src/main/java/entities/FileModel.java
index 13e94499..c50c4ad3 100755
--- a/web/documentserver-example/java/src/main/java/entities/FileModel.java
+++ b/web/documentserver-example/java/src/main/java/entities/FileModel.java
@@ -63,7 +63,7 @@ public class FileModel {
         document.setDirectUrl(isEnableDirectUrl ? DocumentManager.getDownloadUrl(fileName, false) : "");
 
         // get file extension from the file name
-        document.setFileType(FileUtility.getFileExtension(fileName).replace(".", ""));
+        document.setFileType(FileUtility.getFileExtension(fileName));
         // generate document key
         document.setKey(ServiceConverter
                 .generateRevisionId(DocumentManager
diff --git a/web/documentserver-example/java/src/main/java/helpers/DocumentManager.java b/web/documentserver-example/java/src/main/java/helpers/DocumentManager.java
index 90472488..2e4d5dc1 100755
--- a/web/documentserver-example/java/src/main/java/helpers/DocumentManager.java
+++ b/web/documentserver-example/java/src/main/java/helpers/DocumentManager.java
@@ -248,12 +248,12 @@ public final class DocumentManager {
     public static String getCorrectName(final String fileName, final String userAddress) {
         String baseName = FileUtility.getFileNameWithoutExtension(fileName);
         String ext = FileUtility.getFileExtension(fileName);
-        String name = baseName + ext;
+        String name = baseName + "." + ext;
 
         File file = new File(storagePath(name, userAddress));
 
         for (int i = 1; file.exists(); i++) {  // run through all the files with such a name in the storage directory
-            name = baseName + " (" + i + ")" + ext;  // and add an index to the base name
+            name = baseName + " (" + i + ")." + ext;  // and add an index to the base name
             file = new File(storagePath(name, userAddress));
         }
 
diff --git a/web/documentserver-example/java/src/main/java/helpers/FileUtility.java b/web/documentserver-example/java/src/main/java/helpers/FileUtility.java
index e98446a9..1ebc5fd4 100644
--- a/web/documentserver-example/java/src/main/java/helpers/FileUtility.java
+++ b/web/documentserver-example/java/src/main/java/helpers/FileUtility.java
@@ -75,7 +75,7 @@ public final class FileUtility {
         if (fileName == null) {
             return null;
         }
-        String fileExt = fileName.substring(fileName.lastIndexOf("."));
+        String fileExt = fileName.substring(fileName.lastIndexOf(".") + 1);
         return fileExt.toLowerCase();
     }
 
diff --git a/web/documentserver-example/java/src/main/java/helpers/ServiceConverter.java b/web/documentserver-example/java/src/main/java/helpers/ServiceConverter.java
index de29d42e..9c76e84f 100644
--- a/web/documentserver-example/java/src/main/java/helpers/ServiceConverter.java
+++ b/web/documentserver-example/java/src/main/java/helpers/ServiceConverter.java
@@ -158,8 +158,8 @@ public final class ServiceConverter {
         ConvertBody body = new ConvertBody();
         body.setRegion(lang);
         body.setUrl(documentUri);
-        body.setOutputtype(toExtension.replace(".", ""));
-        body.setFiletype(fromExt.replace(".", ""));
+        body.setOutputtype(toExtension);
+        body.setFiletype(fromExt);
         body.setTitle(title);
         body.setKey(documentRevId);
         body.setPassword(filePass);
diff --git a/web/documentserver-example/java/src/main/java/helpers/TrackManager.java b/web/documentserver-example/java/src/main/java/helpers/TrackManager.java
index 5acddef1..83fdae5e 100755
--- a/web/documentserver-example/java/src/main/java/helpers/TrackManager.java
+++ b/web/documentserver-example/java/src/main/java/helpers/TrackManager.java
@@ -150,7 +150,7 @@ public final class TrackManager {
         String newFileName = fileName;
 
         String curExt = FileUtility.getFileExtension(fileName);  // get current file extension
-        String downloadExt = "." + (String) body.get("filetype");  // get the extension of the downloaded file
+        String downloadExt = (String) body.get("filetype");  // get the extension of the downloaded file
 
         // convert downloaded file to the file with the current extension if these extensions aren't equal
         if (!curExt.equals(downloadExt)) {
@@ -164,13 +164,13 @@ public final class TrackManager {
                     // get the correct file name if it already exists
                     newFileName = DocumentManager
                             .getCorrectName(FileUtility
-                                    .getFileNameWithoutExtension(fileName) + downloadExt, userAddress);
+                                    .getFileNameWithoutExtension(fileName) + "." + downloadExt, userAddress);
                 } else {
                     downloadUri = newFileUri;
                 }
             } catch (Exception e) {
                 newFileName = DocumentManager.getCorrectName(FileUtility
-                        .getFileNameWithoutExtension(fileName) + downloadExt, userAddress);
+                        .getFileNameWithoutExtension(fileName) + "." + downloadExt, userAddress);
             }
         }
 
@@ -193,7 +193,7 @@ public final class TrackManager {
         }
 
         // get the path to the previous file version and rename the last file version with it
-        lastVersion.renameTo(new File(versionDir + File.separator + "prev" + curExt));
+        lastVersion.renameTo(new File(versionDir + File.separator + "prev." + curExt));
 
         saveFile(byteArrayFile, toSave); // save document file
 
@@ -236,7 +236,7 @@ public final class TrackManager {
         String downloadUri = (String) body.get("url");
 
         String curExt = FileUtility.getFileExtension(fileName);  // get current file extension
-        String downloadExt = "." + (String) body.get("filetype");  // get the extension of the downloaded file
+        String downloadExt = (String) body.get("filetype");  // get the extension of the downloaded file
 
         Boolean newFileName = false;
 
@@ -265,10 +265,10 @@ public final class TrackManager {
             // new file
             if (newFileName) {
                 fileName = DocumentManager.getCorrectName(FileUtility.getFileNameWithoutExtension(fileName)
-                        + "-form" + downloadExt, userAddress);  // get the correct file name if it already exists
+                        + "-form." + downloadExt, userAddress);  // get the correct file name if it already exists
             } else {
                 fileName = DocumentManager.getCorrectName(FileUtility.getFileNameWithoutExtension(fileName)
-                        + "-form" + curExt, userAddress);
+                        + "-form." + curExt, userAddress);
             }
             forcesavePath = DocumentManager.storagePath(fileName, userAddress);
         } else {
diff --git a/web/documentserver-example/java/src/main/webapp/index.jsp b/web/documentserver-example/java/src/main/webapp/index.jsp
index ca1dbab6..2a95a6f6 100755
--- a/web/documentserver-example/java/src/main/webapp/index.jsp
+++ b/web/documentserver-example/java/src/main/webapp/index.jsp
@@ -367,9 +367,9 @@
         <script type="text/javascript" src="scripts/jscript.js"></script>
 
         <script language="javascript" type="text/javascript">
-            var FillExtList = "<%= String.join(",", DocumentManager.getFillExts()) %>";
-            var ConverExtList = "<%= String.join(",", DocumentManager.getConvertExts()) %>";
-            var EditedExtList = "<%= String.join(",", DocumentManager.getEditedExts()) %>";
+            var FillExtList = "<%= String.join(",", DocumentManager.getFillExts()) %>".split(",");
+            var ConverExtList = "<%= String.join(",", DocumentManager.getConvertExts()) %>".split(",");
+            var EditedExtList = "<%= String.join(",", DocumentManager.getEditedExts()) %>".split(",");
             var UrlConverter = "IndexServlet?type=convert";
             var UrlEditor = "EditorServlet";
 
diff --git a/web/documentserver-example/java/src/main/webapp/scripts/jscript.js b/web/documentserver-example/java/src/main/webapp/scripts/jscript.js
index 5cc6da67..93f40efa 100644
--- a/web/documentserver-example/java/src/main/webapp/scripts/jscript.js
+++ b/web/documentserver-example/java/src/main/webapp/scripts/jscript.js
@@ -100,10 +100,10 @@ if (typeof jQuery !== "undefined") {
         jq("#filePass").val("");
 
         var fileName = jq("#hiddenFileName").val();
-        var posExt = fileName.lastIndexOf(".");
+        var posExt = fileName.lastIndexOf(".") + 1;
         posExt = 0 <= posExt ? fileName.substring(posExt).trim().toLowerCase() : "";
 
-        if (ConverExtList.indexOf(posExt) === -1) {
+        if (!ConverExtList.includes(posExt)) {
             jq("#step2").addClass("done").removeClass("current");
             loadScripts();
             return;
@@ -177,10 +177,10 @@ if (typeof jQuery !== "undefined") {
         jq("#beginView, #beginEmbedded").removeClass("disable");
 
         var fileName = jq("#hiddenFileName").val();
-        var posExt = fileName.lastIndexOf(".");
+        var posExt = fileName.lastIndexOf(".") + 1;
         posExt = 0 <= posExt ? fileName.substring(posExt).trim().toLowerCase() : "";
 
-        if (EditedExtList.indexOf(posExt) !== -1 || FillExtList.indexOf(posExt) !== -1) {
+        if (EditedExtList.includes(posExt) || FillExtList.includes(posExt)) {
             jq("#beginEdit").removeClass("disable");
         }
     };