When two people are using MemInfo, you could run into problems if both people are trying to update the date for the same family at the same time. MemInfo prevents this from happening.
If User-A is updating the Smith page, and if User-B goes to the Smith page, MemInfo won’t let you see that page if you are in “Modify” mode (the Modify button on the Family page is green). You will need to click the Modify button so that it turns blue.
If you get the message (above), click your Modify button to change it from green to blue.
However, problems can occur. If User-A has the Smith page and then disconnects from the server without first leaving the Smith page, you might assume that no one else is editing Smith. But ask around. That other person will need to connect back in to MemInfo and properly exit.
And if that doesn’t fix the problem, then “reindex” the files (File | Setup | Reindex the Files). Just make sure that no one else is using MemInfo before doing a reindex! If you get the message “File access is denied,” click “Cancel” and contact support at 911 at MemInfo.com