The Illinois Freedom of Information Act (5 ILCS 140/), usually referred to as FOIA, provides that all public records must be available for public inspection, unless there is a compelling reason not to release the information. It also specifies state universities as subject to the statute.
The full text of the Act may be found at: http://www.ilga.gov/legislation/ilcs/ilcs3.asp?ActID=85
According to the statute, "Public records" means all records, reports, forms, writings, letters, memoranda, books, papers, maps, photographs, microfilms, cards, tapes, recordings, electronic data processing records, electronic communications, recorded information and all other documentary materials pertaining to the transaction of public business, regardless of physical form or characteristics, having been prepared by or for, or having been or being used by, received by, in the possession of, or under the control of any public body.
FOIA presumes that any public record is subject to public disclosure, unless it falls into one of a few specified categories. Records exempt from disclosure include employee personal information such as home address or personal phone number and email address, or other information that would constitute an unwarranted invasion of individual privacy. It also includes information where disclosure is prohibited by law, such as health information and personal financial information. A record request that is so broad or complex as to place an undue burden on the public body to respond is also exempted from fulfillment.
https://www.uillinois.edu/foia
Office of University Relations - (217) 333-6400
The Campus Administrative Manual (CAM) states the following under its Appropriate Use Policy: (http://cam.illinois.edu/viii/VIII-1.1.htm)
Before storing or sending confidential or personal information, campus users should understand that most materials on University systems are, by definition, public records. As such, they are subject to laws and policies that may compel the University to disclose them. The privacy of materials kept in electronic data storage and electronic mail is neither a right nor is it guaranteed.
With that understanding, the university does make an effort to separate personal information of employees from work product, and has a policy and a process for accessing another person's documents, however users are advised to operate their work computers with the knowledge that the systems are owned by the university and with the assumption that everything on them may be accessed or disclosed at the university's option. If you want assurance that your personal information will not be seen by others, do not put it on your university system.
Outside of the personal information that the FOIA office will exclude from their response, users should assume that everything on a university-owned computer is subject to being disclosed under FOIA.