The error says: This post describes some useful fixes that will help resolve this error. Try one or more of the following:*Check the path to make sure it was typed correctly.*Select a file from the list of files and folders.
This is not a valid file name, Outlook when sending email
We suggest the following fixes if you get This is not a valid file name error in Outlook when sending email: Let us see these solutions in detail.
1] Remove invalid special characters from the file name
If you’ve attached a file with the email, make sure the filename doesn’t contain any special characters that aren’t supported by Outlook. Forward slash (/), backward slash (), pipe (|), and colon (:) are some of the characters that are not part of Outlook’s file naming convention. Remove such characters from the file name and see if it fixes the issue. Also, check the name of the drive in the file path. If it contains any special characters, save the file in a different drive and then try sending the mail. If your email doesn’t include any attachments and you still see the error, refer to the next solutions in the list.
2] Remove hidden/ broken links from the body text
If the mail body contains any hidden or broken image links, Outlook may throw this error. Convert the mail HTML into plain text by switching to the Format Text tab and then selecting the Aa Plain Text option. Fixing broken or hidden links may potentially fix the issue.
3] Run Microsoft Support & Recovery Assistant
Microsoft’s Support & Recovery Assistant helps in fixing issues that users encounter frequently while using Outlook on their Windows 11/10 PC.
4] Run Outlook in Safe mode and disable add-ins
If the above solutions don’t work, try running Outlook in Safe Mode and disable add-ins. An outdated version of an add-in software may sometimes conflict with Outlook and cause it to throw errors.
5] Repair Outlook Data files
The issue may also appear if there’s something wrong with the Outlook Data files (.pst & .ost). These files save messages and other Outlook items (such as calendar events) locally on your PC. If these files contain any corrupt entries, fixing them may resolve the issue. You can use the Inbox Repair tool (SCANPST.EXE) to repair corrupt Outlook PST & OST data files. Read Next: How to repair the Inbox Folder in Outlook.
How do I fix an invalid file name?
To fix the not a valid file name error, you should remove all special characters from the name of the file that aren’t valid in Outlook. Also, look for any spaces before or after the file name. Keep it short and simple. If that doesn’t help, try other troubleshooting tips listed in this post.
What does invalid file name mean?
A file name is said to be invalid if it contains special characters that are not supported by Outlook. Keeping the file name to a reasonable length (under 255 characters including path name) and avoiding special characters such as colon (:), slash (/,), etc., makes it valid in Outlook
