Is this patched 7.4P3 or not?

Yes, 7.4 sp3

today:

Reporting queued error: faulting application save.exe, version 7.4.3.0, faulting module dskquota.dll, version 5.2.3790.3959, fault address 0x000000000000992b.

szAppName : save.exe szAppVer : 7.4.3.0 szModName : dskquota.dll
szModVer : 5.2.3790.3959 offset : 000000000000992b

C:\DOCUME~1\exchange\LOCALS~1\Temp\1\WERdb05.dir00\save.exe.mdmp
C:\DOCUME~1\exchange\LOCALS~1\Temp\1\WERdb05.dir00\appcompat.txt

Message was edited by:
Aleksandr

Yes, I know that it is 7.4SP3, but is it patched? There are different builds of 7.4SP3 out there - which one is yours?

Btw, what is save.exe.mdmp?

I installed 7.4 sp3, but no patches were installed. How can I view the builds no. of my NW 7.4SP3?
Where can I download the patch?

On Windows system you can go to properties of file and then version tab. One of fields there will tell you version. Initial version was build 569. Then patch for that build was released with id of 579. It does fix some of the issues like yours. You may wish to check with support how to get it.