Attention, MNsure shoppers: Avoid the “save and exit” button.

Some applying for coverage through the state’s health insurance exchange this fall have run into trouble if they don’t finish the online process all in one sitting.

After hitting a button to save a partial application and exit, some users have found they must start over when they return to the website.

MNsure spokesman Joe Campbell said Friday he wasn’t sure exactly how many people have had troubles, writing by e-mail: “I’ve heard the number 600 thrown around, but that’s just an estimate.”

Whatever the tally, the issue surfaced this past week in messages to MNsure on social media. Campbell said that the save-and-exit button works in many cases, and that MNsure users, overall, are encountering far fewer glitches this fall than during previous years.

“We have, and will continue to, remind people to always try and complete the enrollment process in a single sitting,” Campbell wrote.

Individuals and families use MNsure to buy coverage from private insurers, and to enroll in state public health insurance programs. Open enrollment for sign-ups in private plans started Nov. 1 and ends Dec. 15 for people who want coverage that starts in January.

As of Tuesday, 17,678 people had signed up for private coverage through MNsure since the start of open enrollment.

“These 600 (or so) people represent 3 percent of completed enrollments so far in this open enrollment period, and a significantly smaller share of people who have been to to shop and compare,” Campbell wrote. “The vast majority of people who come to MNsure experience absolutely no issues whatsoever.”

The issue is described on a tipsheet for users that’s posted to the MNsure website.

The tipsheet also tells users that they: shouldn’t use tablets or smartphones; should clear their browser cache and cookies before signing in; and should only use the Firefox or Google Chrome browsers.

MNsure’s open enrollment period ends Jan. 31. After the December deadline passes, there will be subsequent deadlines for coverage that starts in February or March.