computer crashes and lagging internet

[REDACTED]

Hi.
I purchased Avast Pro for two years on the sixth of this January after the new year. My problem is that since that time I have had 4 blue screen crashes. Opening web pages lag for what seems ages, and I cannot shut down the computer without having to press the button. The computer has been checked for viruses and its checked none.   Mid January I unistalled the program and reinstalled it but have had no improvement so far.

[Asyn]

- Which version of Avast Pro..?
- OS..? (32/64 Bit..? - which SP/Build..?)
- Other security related software installed..?
- Which AV(s) did you use before Avast..?

[REDACTED]

Here's the detail

Avast Pro Antivirus
version:  11.1.2245
OS : Windows 7   64bit
which SP:  Service Pack 1
other AV : Spybot and Zone Alarm.

Last year a tech guy installed Avast.

[Eddy]

Remove Spybot.
The teatimer is not compatible with avast.
Besides that, it used to be a good tool but for several years it has a huge lack of detection.

Also remove Zone Alarm, it is not just a firewall anymore for years.
It also installs (parts of) their av and they can interfere with avast.