Regarding removing the patch ...
One question we always ask, is 'what changed ?'
Usually, the answer in 'nothing'.
Based on this answer we start troubleshooting, only to find sometimes days later that in fact, something was changed ... With that change being anything, OS, patch, NBU config or anything else you can think of.
Of course, having all the info at the start of the problem, would very often shorten the t/shooting process.
In this case, full marks to you as you have explained that something has changed.
Now, if the issue only started after the patch went on, then it is at the very least, reasonable to consider the possibility that the patch is at least part of the problem. It may well be the case that Veritas Engineering need to get nvolved and perhaps it might be found that the MS patch has made a perfectly resonable change, and NBU doesn;t like it, so NBU will need to be fixed.
It is also possible, the the MS patch has changed something 'unreasonable' and that MS need to fix it.
Or, it could be the Veritas will end up needing to talk to MS and come to some compromise - who knows ...
Given the above, it is reasonable to (if possible) remove the patch as a test - to see if it causing the issue, then the relevant parties can get together to find some solution. It is by far the quickedt way to narrow down the issue - as looking at NBU is not going to easiy show the prolem if the issue ihas been caused more at OS level. OF course, sometimes it is not possible to remove a patch, what I would suggest in that case would be to find out exactly what the patch does (and yes, that will probably involve calling MS) and then it may be more clear if it is possible that the patch has caused the issue.
