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Contributor III
Message 1 of 6

Firewall on one computer blocks LAN access

Although this is a new post I have raised a similar, and possibly related, issue, with a lot of configuration info in the post Strange LAN problem, below.

After exhaustive, (and exhausting), investigation it seems that if I fire up one particular box, (Win 7), before any of the others, (Vista, Win 7 and occasionally XP Pro), none of the other boxes can see each other on my LAN.

However, if I fire, up, for example the Vista, or the other Win 7  box first, there  are no problems.

The only way to resolve the non-appearance of network devices is to turn off the Firewall on the 'problem' box.  That allows every box to see every other, and once that has happened  I can turn the Firewall back on again and still retain LAN connectivity.

It surely has to be a McAfee firewall issue on the 'problem' box, because the very act of turning it off resolves the problem.  Nevertheless I have checked the Windows config on the 'problem' box and it all seems OK and indeed, identical with the other boxes.

Any ideas - please.  I beginning to feel that using McAee was a bad decision, even though Dell hooked me with a starter subscription on the three latest boxes.

5 Replies
Former Member
Message 2 of 6

Re: Firewall on one computer blocks LAN access

Sorry for the inconvenince caused, have you already tried adding those IP Address in Firewall settings. If not, please follow the screenshot below and add those IP Address on both computers (for eg.: Ist computers IP to the 2nd one and the 2nd computers IP to the 1st one) and check the status


Contributor III
Message 3 of 6

Re: Firewall on one computer blocks LAN access

No, adding specific IP addresses does not resolve the issue.

There is definitely some bizarre firewall issue because if I turn it off, all works properly.

Even odder, if I fire up either of the Win 7 boxes before I fire up the Vista box I have to go through the 'turn off firewall' ritual to gain full access. However, if I fire up the Vista box first then followed by either of the Win 7 boxes, regardless of sequence, then I have full access.

If I fire up, in sequence, the two Win 7 boxes only, then in one direction I have connectivity issues.  In the other direction, however, not a problem.

I am sorely tempted to dump McAfee on the basis that the firewall just does not seem to work locally.

The annoying thing is that several months ago, before I purchased the second Win 7 box, the network functioned OK.  It all seems to have happened in the fairly recent past with one of the later updates that seem to be regularly streamed down with no more information that that 'your software has been updated'.  Updated is not,perhaps, the word I would have chosen.

There is no meaningful advice on the McAfee Help pages as they still seem to be locked into some time warp for a previous version of the Firewall, and in terms of specific information are depressingly terse. Indeed, when searching the FAQ's it is often impossible to go to page 2 because of an error of some sort.  Returning later seems to resolve that issue and allows access to more, generally outdated, information.

McAfee is turning out to be a very disappointing experience overall - and, to make it worse several friends and colleagues are now offering variations on the theme of 'I told you so' and 'We did warn you!' not to mention other, less repeatable comments.

Contributor III
Message 4 of 6

Re: Firewall on one computer blocks LAN access

I believe this has now been resolved!

Further experimentation on the two Win 7 boxes was focused on the Connections page.

By default this was set to the default IP address range of -, which should have given full access.

Based on information gleaned from a Google search and elsewhere on one of these forums, several days ago I had attempted to change, or rather, edit, the setting to -  (The implication was that 255 may have been out of range, although I am unsure on this point myself.) This was not possible as McAfee flagged up an error message about illegal values.  At that time I dropped that idea and cast around for further ideas.

Today I had the idea of adding a further rule to the Connections page - - to both of the Win 7 boxes.  (This seemed to be an ample and sufficient range.)

Hey presto!

Suddenly the boxes could see each other without any issues.

I then fired up the Vista box - again success!

Finally, in a final fling, I fired up the old X_P Pro box. Further success!

Wonder wonders, joy of joys, everything seems to be functioning correctly and there appears to be  no need to temporarily disable the Firewall anymore

Not sure why this latest 'fix' has (at least so far) worked, but I do recall reading somewhere that it is possible that the default rule does not always register correctly.

Whatever the reason, at the moment I am happy that the issue is resolved.

Former Member
Message 5 of 6

Re: Firewall on one computer blocks LAN access

In fact the screenshot what I have posted above is just to identify the settings. Anyhow, glad to know you got them fixed...

Contributor III
Message 6 of 6

Re: Firewall on one computer blocks LAN access

Hi Aldrin,

Thanks!  Yes I saw the screen shot but as I noted, for some reason, the single IP didn't work as it should.  Thinking back I suspects that I may have inadvertently entered the wrong address.  OK, should have checked, but at least adding the 'new' range works well.

Pity that the default doesn't seem to work.

I also had the incident where I could not access the 'Sharing' tab on any file or folder which was resolved by allowing access to the MSFTDS port, 445.  Now, that particular setting was never needed in earlier versions because I had been sharing files quite happily for a couple of years or so.

Looks as if v11 is a little flaky.  Can you, or do you, feedback to McAfee on these issues?  There seems to be no easy way for us mere users.  No email info in UK and the 'Chat' line is not an attractive option unless you can jump straight to Tier 2 Support.

Ah  well, all's well that ends well.

Best wishes.

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