BleepingComputer.com: Address Was Blocked

Recently I had a problem of not receiving Email. I have windows vista premium. The email problem started soon after I used the Recovery Program. But I don't suspect that had anything to do with it. The first thing I noticed was the alert on the tools menu would indicate that I had mail and when I checked, there was nothing there. Sometimes it would indicate I had two emails when there was only one. Then after a while, I was not receiving any at all. That's when I decided to send an email to myself. Well, I sent a couple and received none. So I got in touch with "Support" and it was discovered that somehow my internet address was placed in the "Blocked Address Area" that prevented any email from reaching my Inbox. Now I know I did not place it there. No one else has access to my computer.
So how in your opinion, can something like this happen. I remember one time that I was online and forgot to activate my antivirus program and am thinking someone got into my computer. But then why mess with my address?
Also if it matters, I use a registry cleaner called "RegCure" and I noticed that the windows security icon is laying on the RegCure Icon. Does that indicate anything? I searched help and there was nothing about this.

The usefulness of cleaning the registry is highly overrated and can be dangerous. In most cases, using a cleaner to remove obsolete, invalid, and erroneous entries does not affect system performance but it can result in "unpredictable results". Unless you have a particular problem that requires a registry edit to correct it, I would suggest you leave the registry alone. Using registry cleaning tools unnecessarily or incorrectly could lead to disastrous effects on your operating system such as preventing it from ever starting again. For routine use, the benefits to your computer are negligible while the potential risks are great.

You may also wish to read the article at this site.

Thanks,
I was using RegCure weekly for at least a year along with scanning and defraging my OS monthly just for preventive maintenance and now I will stop using RegCure but will leave it on my computer for later use if a problem pops up and I cannot fix it. Then it goes into the shop for repairs if the registry cleaner does not fix the problem. This seems to be a good compromise.

Does "RegCure" make backups? If it does, you might check the dates with the time you started having problems with your email. You can restore those backups and see if the problem is solved.