Thank you for your post.
To determine if this is a database file issue, create a new file, pull down the File menu and select Send -> Mail. Send via the Email client, address it to yourself, and put a Subject of "Test". Click OK. Does this work? If so, then create a script that executes the script step "Send Mail". Does this work?
If both steps fail above, and since this previously worked "flawlessly", uninstall and reinstall FileMaker Pro. One or more files may have become damaged.
Keep me updated with any progress.
I tried both of your tests, and it works just fine -- so I guess the problem is with the database file. What's next?
By the way, thanks for the help.
Thanks for the information. This does help narrow down the possible causes.
Open your original database file. Since the Send Mail script occurs with this file, I don't know if the layout that calls the script is a contributing factor, so for now, select a different layout. From there, pull down the File menu and select Send -> Mail, send via the email client, address it to yourself, and put a Subject of "Test". Click OK. If this works, then we know the database file is fine.
Assuming this works, select the layout where the script is usually called, but do not execute the script. Follow the same steps above by sending a Test email to yourself. If this works, then the layout is probably fine.
In case the old script is having an issue, create a new script that simply sends a Test email to yourself, and execute the script. If this works, change one item in the script that matches your original script. That is, if you have a specific Subject, put this in the Send Mail script step, save the script, and execute the script. If this works, repeat with another item from the original script and try again. If you get through all items so that it is exactly as your original script, and it works, then remove the original script (since it is bad) and replace with the new script. However, if you find a specific item that makes the Send Mail fail, let me know.
Continue to keep me updated with any progress.