The first problem is the Registry "booster".  Registry programs, by whatever name they want to call them, can cause more problems than they claim to fix.  We have seen a lot of problems caused by Registry programs here and I've also seen them on clients that I support. 

I have a Dimension E510 which is identical to the 5150.

The temp files will not cause slow booting, either. 

Is the delay or most of the delay the initial bootup and the start of Windows loading or after the start of Windows loading?

Most likely there is either a hardware problem or you need to do a complete reinstall (a "clean" reinstall which involves reformatting the hard drive).  As PC's are used, programs installed, uninstalled, updated, etc the Operating System can get clogged and corrupted and the only real fix is a reinstall.

There is a Dell diagnostic partition on the hard drive, accessed by F12 at Power On.  Run the diagnostics to see if anything shows up.   Run a hard drive, Error Checking and also a disc defrag; although this will not fix a 40 minute startup. 

Start up programs can also clog things up and cause slow Windows startup.  There can be a lot of programs in start up that don't really need to be there.  There can be programs in the Sys Tray (lower right) that also slows full startup.  But, ultimately, if there is no hardware problems the reinstall is the way to go.

You should have the Dell Recovery Partition (PC Restore), accessed by CTRL/F11 at power on and this will restore the PC to the original factory condition and no discs are needed.  This is the best option for a reinstall.

Dell instrutions on how to restore the PC 

Thank you for the detailed reply.

I'll follow your suggestions and keep fingers crossed; I'm a bit scared of the reinstall option!

In the meantime to answer your question: Windows starts to load quite promptly and all the desk top icons appear but the hour glass remains on and there is lots of "hard drive like" whirling noise which lasts for about 40 minutes.  During this time any attempt to start a program results in a painfully low response.

Does that narrow the problem at all?

Noori

It sounds like you have too many start up processes at startup or even a virus or malware.

Do you regularly scan with up to date antivirus and anti-malware programs? Have you defragmented your hdd recently?

You can reduce the number of start up processes by disabling the unecessary ones in msconfig (start>run and type in msconfig)

Thanks for that.  The contents of the startup might well be the related to my problem: there are dozens of programs in there and they are all ticked!  I only recognise a handful of them.  Can I do any damage by disabling "the wrong " program?

Hello noori

Un-checking items on the Start Up tab in msconfig is meant for diagnostic purposes only and should not be used as a permanent fix. It causes Windows to go from a Normal Start Up (on the General Tab) to a Selective Start Up. And it generates a warning message every time Windows boots up. And, yes, you  can do damage if you don't know what you're disabeling. If it's something that Windows needs, your system may not even boot up.

All of these things should be done from an account with Admin. priviledges.

I would download, if you don't already use, MalwareBytes (Free Version). After download, stop the Real-Time protection part of your Anti-Virus program, or close the Anti-Virus program, then install and run MalwareBytes. Some viruses, spyware, ect;, target MalwareBytes specifically and will not let you even install the program. If that happens you are definitely infected and you should go to the "Find out if you're infected" paragraph.
If MalWareBytes does install, click the box to let it run the program and then click Finish. The program should open up and ask if you want to update the data base, click OK or Yes. After the update installs, do a Full Scan. After it has finished, let it fix whatever it finds. It will create a log file that you can access from the Logs tab in the program.

Next I would download and run SUPERAntiSpyware (Free Version). Pretty much the same instructions as above except when the scan stops, everything it found will be in the big window on the left. Make sure everything is checked and click next.This program will also create a Log file.

The Free versions of these programs don't include Real-Time protection. That's OK because you never want more that one program running real time protection.

These things probably won't do anything about all the entries in msconfig. So you will probably need to.......


Find Out If You're Infected

Go to a site like GeeksToGo or BleepingComputer. Click the Forums tab. Find the forum titled "Virus, Spyware and Malware Removal".
You will see a link or a pinned article titled "Start Here" or "Read this Before You Post". Follow the directions there, post your problem, and wait for someone to get back to you. It will probably take a few days but someone will get back to you.

Hope this helps
godawgs

Thanks godawgs.

I have a current McAfee that does regular virus checks and tells me that the machine is clean.  Is it still worth running the additional software that you've mentioned?

Regards

Noori

I would suggest you install the free version of malawarebytes and do a scan.

As for disabling items in msconfig, it will not harm your system and you can easily re-enable any item by rechecking the check box. On my laptop I have disabled everything except video, sound, internet security and touchpad.

Hi noori,

No Anti-Virus, spyware or malware program can catch everything. So yes it is worth running the other programs. And MalwareBytes and SUPERAntiSpyware have a hard time finding some rootkit viruses, thus the suggestion to visit a virus removal forum.

If you decide not to visit the virus removal forums, you also might want to consider downloading and running TFC (Temporary File Cleaner) by OldTimer. The link takes you to the download page. It has a description of the program. TFC does not install itself or add files to the Program Files folder. It sits on the desktop. You run it from there and it will clean the Temp files from ALL user accounts.

godawgs

Thanks godawags & bacillus for clarifying the virus and startup issues.

I'll follow up the virus checking route first!

I'll let you know how I get on in a day or two.

Thanks again for now.

Noori

Go to a site like GeeksToGo or BleepingComputer. Click the Forums tab.

WHY? We have a huge backlog of logs waiting to be handled at those forums.

You will get helped sooner if you use the Malware Removal Forum here at Dell Community.

Please Read This Before Posting On the Malware Removal Forum