I have a tower with a PXE NIC in it and I'm trying to install MT ROS via NetInstall.

The tower has a crossover cable into my laptop which has an IP of 172.16.0.10. I start NetInstall and enable net install assigning the client's IP of 172.16.0.9.

I start the tower up, it boots, gets DHCP from my laptop but then when it tries to TFTP my packet capture reveals...

*The client requests /image
*The server acknowledges the reuqest
*The client gets Error Code, Code: Net defined, Message: TFTP Aborted
*The clientrequests the file again
*The server sends four acknowledgements

Then this four times....
*The client requests /image
*The server gets an ICMP echo of destination unreachable

I did notice that the mask on the client is 0.0.0.0 - is it supposed to be this way?

I downloaded the most recent version of NetInstall on Dec. 5th 2007 and had some problems. It would go through the PXE boot and issue an IP address to the client server, but then after it said:
Loading initrd.rgz...
Ready...
Uncompressing Linux kernel... Ok, booting kernel...
Waiting for drivers...

It would not move from "Waiting for drivers..."

It turns out there was a problem with the version of NetInstall I downloaded. I obtained an older copy of Netinstall and had not problems installing 2.9.50.

Anyone else experience this sort of issue?

Can you tell me what version of NetInstall you got and where you got it so I can try this myself?

I left an important piece of info out of my post. The version I was having trouble with was v3.0rc12 and I downloaded it from Mikrotik's website.

Also spoke with a technician at wisp-router.com who experienced this same issue.

I also expirienced a problem with Netinstall v3.0rc12
The PXE boot runs ok but the netinstall window does not list the the device

Later i googled for an older version of Netinstall (v3.0beta7)
that version did list the device...and installed routerOS

the device is x86 with a Realtek8139 interface

Yes, it could be so.
Try with the latest netinstall available on download page,
http://www.mikrotik.com/download/netinstall-3.0rc14.zip

Using the new version of Netinstall fixed my problem. Thanks for the link!