A SIG file won’t open on your computer. You’re clicking it, nothing happens, or you get an error message. This guide explains exactly what SIG files are and how to open them based on their specific type.
What Is a SIG File?
A SIG file is a digital file with the .sig extension. The problem is that multiple programs use this same extension for completely different purposes. Think of it like the word “bank” – it could mean a financial institution or the side of a river. Context matters.
The .sig extension typically represents one of these file types:
Signature files – Text-based email signatures or digital signature data Broderbund files – Print Shop sign or banner project files
Audio files – Sound data from older audio applications Data files – Settings or configuration information
You need to identify which type you have before you can open it.
How to Identify Your SIG File Type
Before downloading software or trying different methods, determine what created your file.
Check the File Source
Where did the file come from?
- Email program or signature manager = Email signature file
- Print design software = Broderbund project file
- Audio editing application = Sound file
- Game or specialized software = Configuration file
Look at File Size
File size offers clues:
| File Size | Likely Type |
|---|---|
| Under 5 KB | Text-based email signature |
| 5-500 KB | Configuration or settings file |
| 500 KB – 10 MB | Broderbund project or small audio file |
| Over 10 MB | Audio or multimedia data |
Open in Text Editor First
Right-click the file, select “Open with,” and choose Notepad (Windows) or TextEdit (Mac).
If you see readable text, email addresses, or simple formatting, it’s likely an email signature file. If you see gibberish or binary data, it’s a different type.
Opening Email Signature SIG Files
Email signature files are the most common SIG files people encounter.
What They Contain
These files store your email signature – the text block that appears at the bottom of your messages. They include:
- Your name and title
- Contact information
- Company details
- Social media links
- Formatted text and sometimes images
Opening Method 1: Text Editor
Windows:
- Right-click the .sig file
- Select “Open with”
- Choose “Notepad” or “Notepad++”
- Click “OK”
Mac:
- Right-click (or Control-click) the file
- Select “Open With”
- Choose “TextEdit”
- View the content
You’ll see plain text or HTML code. This is normal. The code formats your signature when used in email.
Opening Method 2: Email Client
Most email programs can import signature files directly.
Outlook:
- Open Outlook
- Go to File > Options > Mail
- Click “Signatures”
- Click “New” to create a signature
- Copy content from your .sig file
- Paste into the signature editor
Gmail:
- Open Gmail settings (gear icon)
- Scroll to “Signature” section
- Open your .sig file in a text editor
- Copy the content
- Paste into Gmail’s signature box
Thunderbird:
- Go to Tools > Account Settings
- Select your email account
- Click on the account name
- Check “Attach the signature from a file”
- Browse and select your .sig file
Creating or Editing Signature Files
You can create SIG files with any text editor:
- Open Notepad or TextEdit
- Type your signature information
- Format as plain text or basic HTML
- Save with File > Save As
- Change the extension to .sig
- Choose “All Files” as file type
Opening Broderbund Print Shop SIG Files
Broderbund’s Print Shop software uses .sig files for sign and banner projects.
Required Software
You need Print Shop software to open these files properly. The software is available at Broderbund’s official site.
Opening steps:
- Install Print Shop (version 23.1 or newer for 2026)
- Launch the program
- Click File > Open
- Navigate to your .sig file
- Select and click “Open”
Alternative Methods
If you don’t have Print Shop:
- Contact the sender – Ask for a PDF or image export
- Use a viewer – Some free viewers can display the file contents without full editing capability
- Convert the file – Request the original creator to save it in a different format
Common Issues
Print Shop files from very old versions (pre-2000) may not open in modern software. The file format changed significantly over the years.
Opening Audio SIG Files
Some older audio applications saved sound data as .sig files.
Identifying Audio SIG Files
Audio SIG files typically:
- Range from several MB to hundreds of MB
- Come from audio editing programs
- Won’t open in text editors (show binary data)
Software Options
Try these audio programs:
Audacity (Free):
- Download from Audacity’s official website
- Install and open Audacity
- Go to File > Open
- Select “All files” in the file type dropdown
- Choose your .sig file
- If it doesn’t work, try File > Import > Raw Data
Other options:
- VLC Media Player (can play many formats)
- Specialized audio tools from the era when the file was created
- Contact the person who created the file
Import as Raw Audio
If standard opening fails:
- Open audio editing software
- Select “Import Raw Data” or similar option
- Experiment with these settings:
- Sample rate: 44100 Hz or 48000 Hz
- Channels: Mono or Stereo
- Encoding: 16-bit PCM (try others if this fails)
- Listen to the result
- Adjust settings if it sounds wrong
Opening Configuration or Game SIG Files
Some applications use .sig for settings, saved games, or data files.
Identify the Parent Program
Check your computer for programs that might have created the file:
- Look at the file location (often in a program’s folder)
- Check file properties for hints
- Search your installed programs
Opening Steps
- Launch the associated program
- Look for File > Open, Load, or Import
- Navigate to the .sig file
- Select and open
If you don’t know which program created it, the file may be unusable without that specific software.
Common Problems and Solutions
“Windows Cannot Open This File” Error
This happens when Windows doesn’t know which program to use.
Solution:
- Right-click the file
- Choose “Open with”
- Select “Choose another app”
- Try different programs from the list
- Start with text editors, then others
File Opens But Shows Garbage
The program you chose doesn’t match the file type.
Solution:
- Try a different method from this guide
- Use file identification techniques above
- Ask the file sender which program created it
Security Warning Messages
Your system may warn about opening unfamiliar file types.
Safety steps:
- Only open .sig files from trusted sources
- Scan with antivirus software first
- Avoid .sig files from unknown emails
- When in doubt, ask the sender for clarification
Mac-Specific Issues
Mac computers sometimes hide file extensions.
To show extensions:
- Open Finder
- Go to Preferences
- Click “Advanced”
- Check “Show all filename extensions”
Converting SIG Files to Other Formats
Sometimes converting is easier than opening the original.
For Email Signatures
- Open the .sig file in a text editor
- Copy all content
- Paste into a new document
- Save as .txt or .html
- Use the new file
For Print Shop Files
- Open in Print Shop software
- Go to File > Export or Save As
- Choose PDF or PNG format
- Save with a new name
- Share or open the converted file
For Audio Files
- Import into audio software using raw data method
- Once open, go to File > Export
- Choose WAV or MP3 format
- Save the converted audio
Preventing SIG File Problems
Label Your Files Clearly
When saving:
- Add descriptive names (email-signature.sig, not just signature.sig)
- Include dates or version numbers
- Keep files organized in labeled folders
Document File Sources
Create a simple text file listing:
- What each .sig file contains
- Which program created it
- When you created or received it
Use Standard Formats When Possible
For sharing files:
- Email signatures: Use .txt or .html
- Print projects: Export to PDF
- Audio: Save as .wav or .mp3
This prevents recipients from struggling with .sig files.
SIG File Types and Solutions
| File Type | How to Identify | Best Opening Method | Alternative |
|---|---|---|---|
| Email signature | Small size, from email program | Text editor (Notepad/TextEdit) | Email client import |
| Broderbund project | Medium size, from design software | Print Shop software | Request PDF conversion |
| Audio file | Large size, from audio program | Audacity with raw import | VLC Media Player |
| Configuration | In program folder, varies in size | Parent program | Contact file creator |
Conclusion
Opening a SIG file depends entirely on what type of file you have. Start by identifying the source and checking the file size. Most SIG files are email signatures that open easily in any text editor. For other types, you need the specific software that created them.
The key steps:
- Identify the file type using source, size, and content
- Choose the appropriate opening method
- Use conversion if direct opening fails
- Maintain good file organization to prevent future confusion
When you receive a SIG file from someone, ask what program they used to create it. This simple question saves significant time and frustration.
Frequently Asked Questions
Are SIG files safe to open?
SIG files from trusted sources are generally safe. Email signature files contain only text and pose minimal risk. However, like any file type, scan unknown SIG files with antivirus software before opening. Avoid opening SIG files from unexpected emails or untrusted websites.
Can I open a SIG file on my phone?
Yes, but options are limited. Email signature SIG files open in text editor apps on both iPhone and Android. For other SIG types, you need specific mobile apps. Install a text editor like “Text Editor” (Android) or “Textastic” (iOS) to view basic signature files. Complex SIG files require desktop software.
Why do different programs use the same SIG extension?
File extensions aren’t regulated or exclusive. Any software developer can choose any three-letter extension for their files. The .sig extension became popular because it’s short for “signature” or “sign,” making it appealing to different developers for different purposes. This creates confusion but is common with many file extensions.
Can I change a SIG file to a different format without special software?
For text-based email signatures, yes. Open the file in Notepad, copy the content, paste it into a new document, and save as .txt or .html. For binary SIG files (Broderbund projects, audio files), you need the original program to properly convert the data. Simple renaming doesn’t convert the actual file format.
What should I do if none of these methods work?
Contact the person or program that created the file and ask for specifics about the file type and which software created it. If that’s not possible, try posting the file details (without sharing personal information) in technical forums where experts might recognize the specific format. As a last resort, ask the creator to send the information in a more common format like PDF, TXT, or JPG.
