Start IE and go to Tools-->Synchronise.
Then choose the web pages you want to sync and click on properties. Go to Schedule tab and choose "Sync this favorite using the following schedule", and then click on "Add.". The minimum you can change it to, is every one day.

Pardon but, I was referring to auto-synchronizing my computer clock. Instead of the preconfigured once a week, I'd like to schedule it more frequently.

Oh sorry i didn't understand your point.My mistake.

I'm assuming you are using the builtin w32time service to synchronize with an NTP server?

If so, knowledge base article Q223184 desribes the registry entries that can be used to control the service (this applies to Windows 2000 and Windows XP).

Under the registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters

One of the values is

Period : REG_DWORD or REG_SZ
Used to control how often the time service synchronizes. If a string value is specified, it must be one of special ones listed below.
0 = once a day
65535, "BiDaily" = once every 2 days
65534, "Tridaily" = once every 3 days
65533, "Weekly" = once every week (7 days)
65532, "SpecialSkew" = once every 45 minutes until 3 good synchronizations occur, then once every 8 hours (3 per day) [default]
65531, "DailySpecialSkew" = once every 45 minutes until 1 good synchronization occurs, then once every day
freq = freq times per day

Just change this value to how often. Look and the knowledge base article or post here if this doesn't make sense.

I read your post, then had a look in Regedit to see what mine was set to...except that mine doesn't have that setting. I wondered perhaps if you might have made some sort of error, so checked the KB article, but nope, you'd quoted it correctly - the problem is that according to the article I ought to have 8 entries in the Parameters key, but I only have 4 [not counting the Default entry], & Period isn't 1 of them.

From this, it sounds like it's okay if the value is not there. You should be ba able to just add it in there and reboot for the change to take effect. You can see if it worked by going into "Date and Time Properties" on the "Internet Time" tab, and check what it says for "Next synchronization"...

Tried that - doesn't work.