Is it permissible for an employee to take his salary if he has been relieved of work with the permission of his manager, while the salary continues to be disbursed, knowing that he owns a computer office and sometimes prints work papers when needed?

If your employer releases you from work with his consent, then there is no sin upon you in taking the salary. However, if the manager is an agent, he is not permitted to do so except with the permission of the principal, or if his action is for the benefit of the principal; for example, if the worker is skilled and there is no one like him, and there is a fear of work disruption by his departure. But if that is not the case, then neither the manager nor you are permitted to agree to take a salary without work. Your work in your independent office is not sinful, and printing work papers is either part of your agreed-upon work or a voluntary contribution from you.