Sim
In answer to your question, yes the company can monitor all of the above. The computer, network and internet connection is a business tool that the company is paying and therefore owns and not the employees personal property.
However, under the EU Human Rights Directive you are entitled to the protection of your privacy and this extends to the workplace. As a result you have to agree to waive your right to privacy and acknowledge that your email, internet, phone usage etc. can be monitored. This is often covered in a companies policies. However many companies implement monitoring solutions withour developing the policies and having them signed off properly by staff.
So, without knowing the ins and outs of your case, if your company is monitoring your email or internet usage without you having signed a policy that includes an acknowledgement that you are aware of the monitoring, the comopany is in breach of this directive.
As a consultant in this field I have seen numerous companies get into legal difficulties because they had no policies in place or their policies were not written properly. It is important to note that when deploying a policy you should get staff to sign that they have read and understood the policy. Depending on the size of your organisation you should ensure that your legal and HR teams are involved in any policy development.
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