Viewer of emails with non-latin characters in TO or subject

Hello,

Using java Viewer to convert email files (.msg) to html pages generates wrong characters for TO or subject. In the email user used greek characters for the emails and into the email subject.

My environment is:
java version “1.8.0_451”
Java™ SE Runtime Environment (build 1.8.0_451-b10)
Java HotSpot™ 64-Bit Server VM (build 25.451-b10, mixed mode)

Operating System: Ubuntu 22.04.5 LTS
Kernel: Linux 6.5.0-44-generic
Architecture: x86-64

I attach a demo to reproduce the issue.
groupdocs-viewer-src-email-greek-chars.zip (27.7 KB)

Hello @catalin.croitoru ,

Thank you for your inquiry. We have reviewed your example of using our library but were unable to identify the specific problem with rendering to HTML format. When comparing the generated HTML document with the original opened locally in Outlook (as shown in the screenshot), both documents appear identical, and the incorrect character rendering is observed in two cases. Could you please share with us the results of comparing such documents in your environment, so we can better understand how the original is supposed to look? We will be waiting for your clarification.

Hello @evgen.efimov ,

Thank you for your reply, I’ve demonstrate the issue. I attached 2 projects that process same msg file. One project use aspose-email converter to convert the msg file to html, second use groupdocs-viewer to convert to html the same msg file. The output is correct for convertion with aspose-email but wrong with groupdocs-viewer.

The attached printscreen shows the 2 generated files in paralel, the one on left is from groupdocs-viewer, the one on right is from aspose-email.

groupdocs-email-src-cyrilic.zip (29.7 KB)
groupdocs-viewer-src-cyrilic.zip (44.9 KB)
Screenshot from 2025-09-11 17-43-07.png (116.2 KB)

Thank you for your support.

Hello @catalin.croitoru ,

Thank you for providing the examples. We will do our best to investigate them as soon as possible and will get back to you with the results.

Hello @catalin.croitoru ,

We have reviewed your projects and can confirm that after rendering the file “Re This is a test with cyrillic chars in contacts 2.msg” to HTML using GroupDocs.Viewer, there are indeed issues with incorrect character display in the sender field. We have created a corresponding ticket in our tracking system under ID VIEWERJAVA-4003 and linked it to this forum thread. We will notify you as soon as a new version of the library containing this fix is released.

We would also like to clarify your initial request regarding the file “Email to greek.msg” from your first message. Could you please provide at least screenshots showing how the characters hidden behind the “?” symbols in the “To” and “Subject” fields are supposed to appear, so that we can reference the original?

Hello @evgen.efimov

Here is a printscreen from outlook of Email to greek
Email to greek screenshot.png (10.8 KB)

Thanks

@catalin.croitoru ,

Thank you very much for sharing the screenshot. Our developers will continue investigating this case, and we will inform you as soon as there are any updates.

Hello @catalin.croitoru ,

Thank you for your patience. Our development team has conducted an investigation and found that the source file Email to greek.msg contains corrupted characters in the “To”, “Cc”, and “Subject” fields. All other applications also display these characters, often replaced with “?”. This may have happened during archiving or for some other reason.

Could you please share this file with us again via a direct download link (Google Drive or any other convenient cloud storage)? Alternatively, you may send it directly to me at evgen.efimov@aspose.com.

Additionally, we would like to clarify which version of Outlook you are using to open this .msg file and what International options you have configured. You can check them by opening the file and navigating to:
File → Options → Advanced → International options
and then share them with us as a screenshot.

@catalin.croitoru ,

As a small addition to my previous response: if you receive this email in your mailbox and then simply save it as a .msg file, please try saving it using the type Outlook Message Format – Unicode. According to the RFC specification, email headers must use MIME-encoding (=?UTF-8?Q?..?=). However, if the .msg file is created incorrectly or with a “locale-based” ANSI encoding, GroupDocs will not be able to interpret the Greek characters properly.