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Attachments displaying as "size unknown"

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It's been a few weeks now that majority of my incoming and outgoing attachments display as "size unknown" and cannot be opened. My thunderbird is version 52.3.0. Some attachments sent from an email on the same host go through, others do not. For example, an email coming from a Gmail account to my custom host--the attachment says "size unknown" and I cannot download it. When I log into my email via the host, it's all there. So this is a Thunderbird issue for sure.

It's been a few weeks now that majority of my incoming and outgoing attachments display as "size unknown" and cannot be opened. My thunderbird is version 52.3.0. Some attachments sent from an email on the same host go through, others do not. For example, an email coming from a Gmail account to my custom host--the attachment says "size unknown" and I cannot download it. When I log into my email via the host, it's all there. So this is a Thunderbird issue for sure.

All Replies (5)

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got an anti virus scanning you incoming mail? Try disabling it and see if the attachments appear then as they download. It is unfortunately fairly common for anti virus products to completely scramble attachments. Particularly PDF files.

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I tried disabling my AVG for an hour, that didn't seem to help. Any other ideas?

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If you open Tools/Options/Advanced/General/Config. editor and double-click (toggle) the preference mail.server.default.fetch_by_chunks to false, OK, and restart TB, does it make any difference with received attachments?

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sfhowes said

If you open Tools/Options/Advanced/General/Config. editor and double-click (toggle) the preference mail.server.default.fetch_by_chunks to false, OK, and restart TB, does it make any difference with received attachments?

No, attachments still say "Size Unknown"

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Matt said

got an anti virus scanning you incoming mail? Try disabling it and see if the attachments appear then as they download. It is unfortunately fairly common for anti virus products to completely scramble attachments. Particularly PDF files.

Disabling my scanning (AVG) didn't seem to help. Any other ideas?