Hi

Try to disable SEP on one of the client and then install the driver.

If it gets installed, then on SEPM disable the SEP firewall and then try the installation

open sep client
click on network settings
click on logs
check the rule which is blocking it
all the same in firewall policy inside symantec endpoint manager
if not try removing NTP and instal the driver
add/remove programs
select sep , select modify
remove NTP complete the install
check if you are able to install

Disable Symantec Endpoint Protection and SMC services
    Start > Run > smc -stop
    Start > Run > services.msc
    Right-click "Symantec Endpoint Protection" and select Stop

Install the printer

Re-enable Symantec Endpoint Protection and SMC services after the installation finishes
    Start > Run > Services.msc > Right-click "Symantec Endpoint Protection" and select Start
    Start > Run > Services.msc > Right-click "Symantec Management Client" and select Start

We had a somewhat simillar problem where a PC could not be connected to a shared printer. Now, funny thing about this was that client could connect to some but not all of printers on our print server. Don't remember the exact wording of the error message but it was something about current account not having sufficient privileges. This would happen even if an account with domain admin privileges was used. We started having this kind of problems after application and device control policy as described in "Hardening Symantec Endpoint Protection with an Application and Device Control Policy to increase security" (http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2010050810365948) have been intoduced. Fellow admin resorted to removing SEP, installing drivers and reinstalling SEP but I found this to be cumbersome and impractical..

Starting point was insuficient access rights to %WINDIR%\system32\spool folder as indicated by the error message. Removing the spoolsv entry from "Prevent vulnerable Windows processes (lsass, spoolsv, csrss, smss) from writing code" section did the trick. With this setting out of the way now all workstations can connect to any and all shared printers.

I will keep an eye on the logs just to make sure this easy solution won't create more problems than it had solved. So far so good ...

This solution may not work in your scenario but won't hurt if you try.