Steve, I get somewhat the same error e-mail every day. I double checked that the downloaded file is correct and sure enough it is. I saw Cyrus Bharda's post, but do not know if squidguard is actually updating the blacklist.
Have you had any luck tracking this down?
I am running SME 5.6UDR-U4. Here's what I receive each day for the error e-mail:
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/etc/cron.daily/supdate.cron:
04:05:21 URL:
ftp://ftp.teledanmark.no/pub/www/proxy/squidGuard/contrib/blacklists.tar.gz [430127] -> "blacklists.tar.gz" [1] tar (child): blacklists: Cannot read: Is a directory tar (child): At beginning of tape, quitting now tar (child): Error is not recoverable: exiting now
gzip: stdin: unexpected end of file
tar: Child returned status 2
tar: blacklists.tar.gz: Not found in archive
tar: Error exit delayed from previous errors
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I searched the forums and this appears to be the only thread that mentions this problem specifically.
Tom