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cannot delete attachment file with multibyte UTF8 name

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Hi,

I'm using Thunderbird with Courier-IMAP server. When I upgrade Courier-IMAP to 5.0.x, an attachment file with UTF-8 filename cannot delte with error:

 "WRITE: ## NO [ALERT] Your IMAP client does not appear to correctly implement Unicode messages, see https://tools.ietf.org/html/rfc6855.html"

Because Thunderbird add a mime-part with delete comment like: <<<<< BEGIN >>>>>


B9BFA3413B08F1FAB3A2AAC0

Content-Type: text/plain; charset=UTF-8; x-mac-type="0"; x-mac-creator="0";

name="=?UTF-8?B?44OG44K544OILnR4dA==?="

Content-Transfer-Encoding: base64 Content-Disposition: attachment;

filename*=utf-8%E3%83%86%E3%82%B9%E3%83%88%2E%74%78%74

44OG44K544OI <<<<< END >>>>>

I'm not sure this part is violate RFC or not. And I also ask Courier-IMAP developper.

Best regards,

Hi, I'm using Thunderbird with Courier-IMAP server. When I upgrade Courier-IMAP to 5.0.x, an attachment file with UTF-8 filename cannot delte with error: "WRITE: ## NO [ALERT] Your IMAP client does not appear to correctly implement Unicode messages, see https://tools.ietf.org/html/rfc6855.html" Because Thunderbird add a mime-part with delete comment like: <<<<< BEGIN >>>>> --------------B9BFA3413B08F1FAB3A2AAC0 Content-Type: text/plain; charset=UTF-8; x-mac-type="0"; x-mac-creator="0"; name="=?UTF-8?B?44OG44K544OILnR4dA==?=" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename*=utf-8''%E3%83%86%E3%82%B9%E3%83%88%2E%74%78%74 44OG44K544OI <<<<< END >>>>> I'm not sure this part is violate RFC or not. And I also ask Courier-IMAP developper. Best regards,

All Replies (1)

Sorry, I copied attachment Mime-part of original above. When I remove attachment, Thunderbird try to save a new message which have raw text in MIME header like:


5F5AD0058999A55C70504EF7

Content-Type: text/x-moz-deleted; name="Deleted: テスト.txt" Content-Transfer-Encoding: 8bit Content-Disposition: inline; filename="Deleted: テスト.txt" X-Mozilla-Altered: AttachmentDeleted; date="Sun Dec 02 12:15:08 2018"

You deleted an attachment from this message. The original MIME headers for the attachment were: Content-Type: text/plain; charset=UTF-8;

name="=?UTF-8?B?44OG44K544OILnR4dA==?="

Content-Transfer-Encoding: base64 Content-Disposition: attachment;

filename*=utf-8%E3%83%86%E3%82%B9%E3%83%88%2E%74%78%74



5F5AD0058999A55C70504EF7--

And Courier-IMAP 5.0.x rejects the replacement message.

I also ask about this bug to Courier-IMAP deveropper. Please refer:

https://sourceforge.net/p/courier/mailman/message/36481538/

Best regards,