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Group Docs Issues

We are facing following issues regarding preview of documents :-

1) 1) The attached ppt file is not getting previewed as format of the document changes and also the image quality is not good.

2) 2) Any Excel (.xls&xlsx) files are not previewed properly. The format does not display as per the excel as no row & columns are there.

3) 3) Image files quality is not good.

4) 4) If a document contain tables with (:) the colons are not displayed properly.

5)5) In a docx document if we enter tick image sign and cross image(X) sign the tick image is replaced with char ‘a’.

<!–[if gte mso 10]> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:8.0pt; mso-para-margin-left:0in; line-height:107%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}



Hello Sumit,

We are sorry to hear that you have these issues. We’ve downloaded and investigated the two files that were inside the archive - “AA9395.pdf” and “Document matrix.xlsx”. Both files are displayed correct in the image-based and HTML-based modes. We checked them in the Mozilla Firefox, Google Chrome, Opera and Internet Explorer - documents are displaying perfectly.

If there are problems with the image quality, make sure that you have a “Quality(100)” method used. Or, alternatively, you can use HTML-based rendering mode, which doesn’t have quality-related problems at all.

Maybe you are using the old version of the GroupDocs.Viewer - please check this out and download the newest version 2.3 if needed.

If there are some other files which are displaying incorrectly while using the version 2.3, please send them to us.



The issues you have found earlier (filed as WEB-1090) have been fixed in this update.

This message was posted using Notification2Forum from Downloads module by groupdocs.notifier.


Dear Denis,

We are using the latest version,of dll but its nt working properly if you can share the screen shoot of your application and source code. Because we have tried this in your online viewer as well but its not working at all.



Hello Sumit,

Sure, np.

We’ve used standard code in the ASP.NET MVC project that is below:
.FilePath(“Sumit_Documents/Document matrix.xlsx”)

For image-based engine “UseHtmlBasedEngine(false)” method was used, and for HTML-based engine - “UseHtmlBasedEngine(true)”.

Here are screenshots which were captured from the Internet Explorer 10.


Document matrix.xlsx

GroupDocs.Viewer for .NET ver. 2.3.5375.29223

If you will have more questions please feel free to contact us.



As you can verify the xlsx document there is difference b/w htmlbased and imagebased in html based its displaying correct signs under “Jap” column and in image-based its not displaying correct as under “Jap” its displaying ‘a’ instead its should display the correct sign.


Hello Sumit,

Yes, you are absolutely right, thanks. My fault, due to my inattention I hadn’t noticed it before. This document was sent to the developers, when there will be any news regarding it, we will notify you in this forum thread.



Hello Sumit,

Our developers have performed a large investigation with your Excel “Document matrix.xlsx” file. Here is a result.

First of all, the tickmarks are shown correctly (in a form of a tickmark) only in the Internet Explorer and only using the HTML-based mode. In the Internet Explorer when using image-based mode, and in all other browsers regardless the rendering mode, tickmarks are shown incorrectly, in a form of a symbol “a”.

We have evaluated this issue further. We found that it is not an issue with the GroupDocs.Viewer rather a missing font issue. GroupDocs.Viewer needs required fonts to be installed before rendering, so you need to install the required font on the system before rendering. We checked “Document matrix.xlsx” file contains characters of Marlett font, so you got to install “marlett.ttf” font on the system before rendering. I did install the “MARLETT.TTF” font into my Windows/Fonts and then process the following code segment, it works fine.

Moreover, regarding HTML-based rendering, well, font tables are actually rendered by your browser types (w.r.t. fonts.htm – CODE, Hex, CHAR, bold, symbol, webdings, wingdings, wingdings 2, wingdings 3). We found, with Firefox or other non-IE browsers, they can’t render the character fonts properly, so you are getting this issue in non-IE browsers, you may check the Font tables page for replacement tokens for the suppressed characters 128-143 (x’80’ - x’8F’) for your reference.

For example, open the web-page “Symbols for HTML and Excel use”, scroll down to the “Checkmarks, Tickmarks (#ticks)” section and find the symbol with the “0x61” Hex code. Take a look at the “Symbol” column. If you can see the tickmark, then your browser is Internet Explorer, or you have already installed the required font. Otherwise, you should see a “a” symbol in this column.

If you will have more questions please feel free to contact us.