Follow the instructions below to identify and remove those characters:
- Open the file for translation in Trados Studio-> Editor view
- Use Batch Tasks > Pre-translate files using an empty new TM and select the option When no match found > Copy source to target
- Re-open the file and Select all the segments then right click the first and Change Segment Status > Translated
- Run the Update Main Translation Memory task to update the TM with the content from the file
- Re-open the file and Select all the segments then Clear Target Segment
- Start from the first segment and press CTRL+Enter to confirm the TM match. Studio should move automatically and translate all the segments until it reaches the one with invalid characters
- Copy the faulty source segment from Trados Studio in Notepad++ to identify the broken character
- Open the Word source file and remove the character or the whole sentence affected and re-type its contents
- The new file should work fine when recreating the project.
