DTLite.exe 100% processor usage

[CluelessDaemon]

Hi there,
I signed up to the forum because Google did not turn up any useful results and this forum cannot be searched without registration.
I was searching for the word "processor" in three sub-forums:
- Common Problems and Solutions
- Daemon Tools Bug Report
- Daemon Tools SUPPORT
I opened quite a few posts that had a topic title resembling my problem, but in the end, I did not find anything similar.

I have XP SP3+all the hotfixes available on WinDOS update.
I am running DT Lite 4.35.6.0091, SPTD 1.74.

I noticed quite a while ago (not specific to the DTLite version I have installed right now) that the processor usage goes up to 100% every now and then.
I did not pay much attention to it because I expected that someone else would report this problem, and the next release would not have this problem. It's been a long time, and there's no fix yet, so here I am.

I said 100%, because I have an E8500 (dual-core Intel), and task manager shows 50%; I guess you would see 25% on a quad-core system, and so on.

I did not find any particular reason for the extremely high processor usage (no other process uses the CPU that much); I just start my computer, and it goes to 100% right away.
I have only one virtual drive (mapped to drive W).

The thing that I did notice is that DT does this periodically. I did not find a system yet, but I'll start marking the days today, maybe that helps.
It does not seem to matter whether
- there's an image mounted, or not
- I reboot my computer, or not
I attached two screen shots of the task manager.
One showing the processor usage graph (notice the symmetry; always 50%), while the other showing the processes, DTLite.exe is highlighted.

Is this a known issue?
Did I miss another thread somewhere else?
If not, it seems that I am the only one with this problem.
Any clues how to track down the problem?
I would like to have it fixed; the box is heating the room a lot and consumes a lot of power for nothing.
Thank you.

[Blazkowicz]

That is surely a very strange issue.
In your boot.ini is there a /usepmtimer ? If not, please add it at the end.
So it looks like "/EXECUTE /USEPMTIMER " at the end (also try the /execute switch). If the issue isn't gone then, please send a message to support with a link to this thread, thank you.

[CluelessDaemon]

Hi, thank you for the suggestion.
This is my boot.ini:

[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINXP
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINXP="Microsoft Windows XP Professional" /noexecute=optin /fastdetect /usepmtimer

Isn't the /execute switch potentially unsafe?
Now it's 01:14 (and it is Sunday now) and processor usage is normal (zero, that is).
Dumb question: does DT do any maintenance tasks on Saturday (such as defrag its own files, self-test, check for updates)?
In any case, I will wait until this happens again, then give the /execute switch a go.
Thank you.

[Blazkowicz]

DEP is only disabled with /execute switch.

DT doesn't do any maintenance tasks.
Automatic update check shouldn't be 50% processor usage.

[CluelessDaemon]

It's Tuesday (12th of October).
Processor usage is high again.
- I reboot the PC: processor usage is still high.
- I add DTLite.exe to the DEP exceptions (see attachment DEP1) and reboot: processor usage is still high.
- I change DEP setting to limit to essential service only (see attachment DEP2) and reboot: processor usage is still high.

So, there is no way to fix this without disabling DEP as a whole.
I would not want to be force to disable DEP. No other application/service requires such drastic measures. Apparently, there must be a reason for this. Wouldn't it be possible to change the DT not to require disabling DEP?
Thank you.