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One of your filters uses a custom header that contains an invalid character ....

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  • Last reply by Magini

Magini
Magini
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When I send an email the following error message is displayed:

"One of your filters uses a custom header that contains an invalid character, such as ':', a non-printable character, a non-ascii character, or an eight-bit ascii character. Please edit the msgFilterRules.dat file, which contains your filters, to remove invalid characters from your custom headers."

This is followed by a message saying that the email has been sent and saved despite the error.

The problem happened after transferring to Windows 10 (from Win 7)

I have deleted ALL msgFilterRules.dat files and ALL filters, but the message persist.

Any suggestions on what else to try?

Thanks, Ben

When I send an email the following error message is displayed: "One of your filters uses a custom header that contains an invalid character, such as ':', a non-printable character, a non-ascii character, or an eight-bit ascii character. Please edit the msgFilterRules.dat file, which contains your filters, to remove invalid characters from your custom headers." This is followed by a message saying that the email has been sent and saved despite the error. The problem happened after transferring to Windows 10 (from Win 7) I have deleted ALL msgFilterRules.dat files and ALL filters, but the message persist. Any suggestions on what else to try? Thanks, Ben

Chosen solution

Problem solved.

After deleting all imap mail folders/entries the problem went away.

Read this answer in context 👍 0

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Magini
Magini Question owner
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Chosen Solution

Problem solved.

After deleting all imap mail folders/entries the problem went away.