Mal/JavaJar-A was found on my Vista machine, but the free tool is unable to remove it.

Hello Jack and WBell,

if you look at the analysis http://www.sophos.com/en-us/threat-center/threat-analyses/viruses-and-spyware/Mal~Javajar-A/detailed-analysis.aspx it says that it is a generic detection and that files of this type usually attempt an exploit. Subverted Java archives are not uncommon but only pose a danger if one runs a vulnerable Java version. Most of the time the Java cache is neither cleared nor actually reused.
If you run a full scan such items will be discovered (and detection items are never withdrawn, so even when a threat can no longer be called a real one it is nevertheless detected). Now a Jar is - as the name says - an archive. It is not in all cases possible to remove an item (or parts of it) from an archive without corrupting it. The cleanup routine plays it safe and does not act if it's not sure.
Java cache items can safely be deleted.
The other item is a registry key - if used it tells (Microsoft) programs which "types" of attachments can be "safely" opened. The values are extensions considered to be of low risk so e.g. Outlook can assume it safely request the attachment to be displayed. The benefit (and validity) if the entries there is questionable and as this key is sometimes modified by malware of the mentioned type it is flagged. Here again cleanup can neither delete the key without the risk of side effects nor restore it to some safe known value. Only if it finds an extension here which is exclusively used by malware it can delete this value.
I'd simply delete this registry key.

It's not a defect but more a philosophy - be a little bit paranoid when detecting but prudent when cleaning up (and how else would wisecracks like me have an opportunity to lecture)

HTH
Christian

Hello Jack and WBell,

if you look at the analysis http://www.sophos.com/en-us/threat-center/threat-analyses/viruses-and-spyware/Mal~Javajar-A/detailed-analysis.aspx it says that it is a generic detection and that files of this type usually attempt an exploit. Subverted Java archives are not uncommon but only pose a danger if one runs a vulnerable Java version. Most of the time the Java cache is neither cleared nor actually reused.
If you run a full scan such items will be discovered (and detection items are never withdrawn, so even when a threat can no longer be called a real one it is nevertheless detected). Now a Jar is - as the name says - an archive. It is not in all cases possible to remove an item (or parts of it) from an archive without corrupting it. The cleanup routine plays it safe and does not act if it's not sure.
Java cache items can safely be deleted.
The other item is a registry key - if used it tells (Microsoft) programs which "types" of attachments can be "safely" opened. The values are extensions considered to be of low risk so e.g. Outlook can assume it safely request the attachment to be displayed. The benefit (and validity) if the entries there is questionable and as this key is sometimes modified by malware of the mentioned type it is flagged. Here again cleanup can neither delete the key without the risk of side effects nor restore it to some safe known value. Only if it finds an extension here which is exclusively used by malware it can delete this value.
I'd simply delete this registry key.

It's not a defect but more a philosophy - be a little bit paranoid when detecting but prudent when cleaning up (and how else would wisecracks like me have an opportunity to lecture)

HTH
Christian