1️⃣ Basic Checks Before Troubleshooting

• 📄 Verify the file extension matches the program you're using
• 🔄 Restart your device — temporary glitches can block file access
• 💾 Ensure the file isn’t locked or read-only
• ☁️ If downloaded, make sure the file wasn't corrupted during transfer

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2️⃣ Windows Troubleshooting

2.1 ⚙️ Open with Correct Program

1. Right-click file → Open with → Choose correct application
2. Install or update the software that supports the file type (Adobe Reader, Microsoft Office, etc.)

2.2 🔧 Repair or Recover Files

1. Office files → Open → File → Info → Repair
2. PDF files → Use Adobe Acrobat Repair or tools like PDF Repair Toolbox
3. Image files → Use Stellar Repair for Photo or PixRecovery

2.3 🛠️ Convert Unsupported Files

1. Use converters such as Zamzar or CloudConvert
2. Ensure the new format is supported by your software

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3️⃣ Mac Troubleshooting

3.1 ⚙️ Open with Correct App

1. Right-click → Open With → Select compatible app
2. Install required apps from the App Store if missing

3.2 🔧 Repair Files

1. Office for Mac → Open → File → Repair
2. Use Preview for PDFs/images → Export to another format

3.3 🛠️ Convert File Formats

1. Use File Converter or CloudConvert
2. Always keep a backup before converting

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4️⃣ Linux Troubleshooting

4.1 ⚙️ Open with Compatible Program

1. Right-click → Open With → Choose software (LibreOffice, Evince, GIMP)
2. Install missing apps: sudo apt install libreoffice

4.2 🔧 Repair Files

1. Convert Office files with CLI: soffice --convert-to pdf file.docx
2. Fix images with ImageMagick: convert corrupted.png fixed.png

4.3 🛠️ Check Permissions

1. Check permissions: ls -l filename
2. Adjust if needed: chmod 644 filename

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📜 Summary Table of Actions

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