Outlook 2013 - Signature is squished in Signature editor

In Outlook 2013, when myself or any colleague paste a signature into the Signatures and Stationery window in Outlook 2013, it comes in displaying correctly, and the signature displays correctly when composing an email. But if I go back into the Signatures and Stationery window to edit the signature, the contents of the signature are squished into about 35 pixels width. This makes it virtually impossible to edit.

The signature comes from an HTML page we created for the purpose of copying-and-pasting into an Outlook signature. None of us had this problem with Outlook 2010, so appears to be a problem with Outlook 2013 specifically. The HTML contents is basically a single one-column table with a couple of nested tables, with some images and links. It's pretty basic HTML. I tried adding an explicit width to the table, but that didn't help. I've seen a couple of other people bring this up, but haven't found a solution yet (link #1, link #2).

Edit: Per request from @sunk818, here's a link to the HTML I'm using (some identity info blanked out, but structure is the same). And below shows what it looks like in the Outlook 2013 signature editor after saving once, closing the window and re-opening to edit.

This answer is an addition to SPYDOR's answer which is on point ...

You can find your signatures in the folder %userprofile%\AppData\Roaming\Microsoft\Signatures (on the Windows platform).

You will find an HTML (foo.htm), a Rich Text Format (foo.rtf), and a plain text (foo.txt) version of each signature you have. You will have to edit all the three versions if you want to make a change to the content, but for the OP's problem, it is enough to edit only the HTML file. You can edit it using a plain text editor (such as Notepad) or with a WYSIWYG HTML editor, however for the surgical changes you need to make in order to fix this particular problem, it might be a better idea to use a plain text editor.

Another remark is that Outlook will stretch width="100% elements once their parent element have an explicit width declared (but not before). Thus you might have to delete some of the width="100% parameters (and the corresponding style='width:100%' definitions) if you notice that some table cells are stretched against your wish after applying explicit widths to their containing cells.

I just posted a simple solution to this problem in a thread here:

https://answers.microsoft.com/en-us/msoffice/forum/msoffice_outlook-mso_win10/adding-a-signature-to-outlook-2016-formatting/474cf3fc-8e78-4516-b348-4ff369926f58

In your case all you need to do is set the <td style="width: ##"> value for each data cell in the table. You don't need to bother setting the width for the table or the table-rows.

For a copy of the full solution from the link provided, please see below:

- Description -

In the e-mail signature preview window for Outlook 2013 and Outlook 2016, HTML and Rich-Text Format (.rtf) signatures containing tables can appear squashed into a stretched, narrow column in the left of the window, leaving the rest of the preview window empty.

- Cause -

The problem occurs in Outlook 2013 & 2016, when you have a table in your signature and you have not set the 'width' property for the table's individual cells. The previewer in the newer versions of Outlook defaults to a small width (about 10 or 20 pixels) for table cells that do not have the 'width' attribute set.

As the older versions of Outlook did not exhibit this problem, it is likely they defaulted table cells to 100% width in the preview window, when no 'width' property was set. Signature files created in the older versions of Outlook, with no 'width' attribute still exhibit the preview problem in the newer versions. This confirms the problem lies with the preview component.

- Solution -

You simply need to make sure every table cell has a 'width' attribute set.

Fixing Rich-Text Format (.rtf) signature tables

If you have copied & pasted your signature from a Word document then this is the easiest way to fix it.

1. Open the Word document containing the signature table. You can make it easier to see the table layout by clicking on the table, select the 'Layout' tab at the top, then choose 'View Gridlines' from the 'Table' group.
2. Highlight all the table cells then right-click on them, or edit each cell individually if you prefer.
3. Select 'Table Properties...' choose the 'Cell' tab and set 'Preferred Width' to a specific percentage or size.
4. Click 'Ok' to apply the changes. Now copy the fixed signature table into Outlook.

Note that the signature table will always appear correctly as soon as you paste it in, even with no 'width' attributes set. You must close the signature window then re-open it to confirm you have resolved the issue successfully.

Fixing HTML signature tables

If you have created your table using HTML tags, all the <td> tags require a width attribute, using either the percentage or pixel width, as in the HTML5 compliant example below:

<table>
     <tbody>
            <tr>
               <td style="width: 100%">table cell 100 percent wide</td>
            </tr>
            <tr>
               <td style="width: 150px">table cell 150 pixels wide</td>
            </tr>
      </tbody>
</table>

Note that the <table> and <tr> tags do not require a width to be set to resolve this issue.

Once this is saved make sure you re-open the signature window to check your code changes have worked.