Sugar Version 5.2.0g (Build 5731)
LAMP (PHP v. 5.2.5, Apache/1.3.39, MySQL 5.0.45-community)

Yesterday my users lost access to their own accounts (those assigned to them). We use roles in which users can only view, modify accounts assigned to them. In List View the User column correctly shows the assigned user. In Detail View and Edit View the Assigned to: field is now blank. I tried to reassign an account in Edit View but after saving it still shows blank. I exported a user's accounts and looked at the fields in Excel. The user id and username fields are both populated. I cannot figure out where the permissions issue is coming from.

When a user tries to access an Account the following msg appears:
You do not have access to this area. Contact your site administrator to obtain access.

The last thing I did before noticing this issue was to create a custom field in Accounts. There were already existing Accounts in the database prior to the creation of the custom field. I then imported more Accounts that included the new custom field. I don't see how that could cause the problem but I include the info. as it is the last thing I did.