I’m a big fan of ISA and have been since 2000, yes even 2000. Many things have changed since then and mostly for the better. Layer 7 application filtering is a concept that has been around since the beginning and is one of the reasons ISA is a powerful firewall solution. The management of app filter behavior has gone from front and center to somewhat hidden, hence the purpose of this post. App filters provide the ability to control aspects of specific protocols that pass through the firewall: FTP, HTTP, RPC, SMTP, DNS, etc.

If you enable the FTP and HTTP filters on a general outbound internet access policy, the affects of the filters in default form can be quite limiting, especially for FTP. You can edit the policy’s filter behavior one of two ways: right-click context menu on the policy item, or via the filtering button on the Protocols tab in the policy item itself.

The default mode of the FTP filter is read only so you will be able to log into an external FTP site, execute dir/ls commands but transfers to or from will fail. Uncheck read only from the FTP protocol policy to enable full FTP functionality through the firewall. This behavior can be frustrating to troubleshoot if you don’t know where to look, especially since the configuration of the app filters is not particularly obvious.

The Windows 7 Release Candidate finally dropped and if you’re like me you’ve already installed it on every machine you own. =] A problem that I have had since Beta 1 is support for my HP OfficeJet V40xi. This is an all-in-one printer/fax/copier that is almost a decade old now but solid and stable as a rock. Vista has the drivers for it but none of the versions of Windows 7 have so far. HP hasn’t made a driver for this printer since XP. I also have a ReadyNas NV+ which serves as my print server so I connect to the the V40 via my NAS. Unfortunately the NAS doesn’t store and serve drivers so these have to be installed independently. Here is a work-around to get your legacy printer working with Win7 if both Microsoft and your printer manufacturer have abandoned your device.

Before you rebuild that last Vista PC, navigate to C:\Windows\System32\DriverStore\FileRepository\ and search for “prnxxx…” where xxx is your manufacturer and in my case prnhp001.inf_2ade4966 holds the drivers I need. Copy this folder off to a thumb drive or somewhere else safe. On your Win7 machine, connect to the legacy printer and when prompted for drivers point to the INF stored in this folder. Find your printer in the resulting list, let the system install your drivers, and you will be able to use your ancient printer on the next-gen OS. Cheers. :)