Q: Are you using an imap or pop mail account?

If Imap: Q: Can you see the 'Drafts' folder ? Make sure it really is 'subscribed'

• Right click on imap maila ccount and select 'Subscribe'
• select the 'Drafts' folder and click on 'Subscribe'
• click on 'OK'

Enable 'Folder pane columns' if not already enabled.

• 'Menu icon' > 'Options' > 'Layout' > select 'Folder Pane Columns'

In Folder Pane:

• select to see 'Total' and 'Size' columns

see image below as guide.

Q: How many emails are in the 'Drafts' folder? Q: What is the size of the folder? Q: Do you compact the Drafts folder on a regular basis?

Compact the folder to remove all the 'marked as deleted' hidden emails:

• Right click on 'Drafts' folder and select 'Compact'
• Did the 'size' reduce ?

Open a new 'Write' message, type something and save as draft. Q: Did it save much easier.

Thanks for suggestion It's IMAP. Only 11 messages were in Draft. Compacted it; removed one large message of 6mb, so now down to 10 messages. Still will not save messages into Draft. Has been working OK for years until now! CannotsaveDraft

Unsubscribe from seeing Drafts folder.

• Right click on imap mail account and select 'Subscribe'
• select the 'Drafts' folder and click on 'UnSubscribe'
• click on 'OK'

Restart thunderbird.

Subscribe to seeing Drafts folder.

• Right click on imap maila ccount and select 'Subscribe'
• select the 'Drafts' folder and click on 'Subscribe'
• click on 'OK'

Account Settings:

• right click on imap mail ccount and select 'settings'
• Select 'Copies & Folders'
• Keep message drafts in:
• Select 'Other'
• Select 'Drafts folder on imap mail account'
• Click on OK

Restart Thunderbird. open a new Write message, type something and try save to drafts.