InformationWeek readers know their users store e-mail on local drives, but aren't sure if they approve.Sixty percent of respondents to an InformationWeek survey on e-mail archiving say their users store .pst files on their own computers and removable drives. Outlook allows users to save messages, calendar entries, tasks, and other information in a personal folder on the local machine called PST. From there, these files can be moved to shared drives and removable media.

Users like PST files because they can read stored messages when they aren't connected to Exchange, and because they can have local copies of messages with important business information.

However, only 34% of respondents expressly allow PST files, while 31% don't have a policy. (In case you're wondering, 864 business technology professionals responded to this survey.)

Why should you care? If you guessed electronic discovery and compliance, you've been paying attention to this Information Management blog. PST files are a risk. For one, if your organization has retention/disposition policies in place, PST files let users get around those polices. Locally stored messages also may contain sensitive data that could lead to a breach if a user's laptop is lost or stolen.

PST files also complicate electronic discovery efforts. Discovery activity may overlook potentially relevant messages buried on a user's hard drive or flash drive. Users may delete incriminating messages -- activity the courts frown on.

Are PST files on your radar? Thirteen percent of respondents say they are developing a policy, and 11% said they didn't know if their organization had a policy regarding PST files.

Are you able to balance the risks with user demands? Or do you think the issue is overblown? Let us know.

The full survey results will be available in a forthcoming InformationWeek Analytics Report.