Why can't I login with a workbook that was created before I upgraded to Sage 300 Construction and Real Estate 9.5 or 9.6?

Background
Previous versions of Sage 300 Construction and Real Estate identified data folders using a path beginning with a drive letter.  In a network environment, this would be a drive letter mapped to a location on a file server (e.g., T:CompanyXYZ).  Beginning with Sage 300 Construction and Real Estate 9.5, network data folders are no longer identified using a mapped drive letter path.  Instead, the UNC (Universal Naming Convention) path is used.  This identifies the server name and location on the server of the data files (e.g., \STOServerDataFilesCompanyXYZ).  Permission must be granted for non-admin Timberline users to each data folder and this security information is stored in Timberline by UNC path.  This means that an attempt by a non-admin user to access data via a mapped drive letter path will not work because the former mapped drive letter paths do not appear in the list of data folders that permission can be granted for.

Symptom
After upgrading from Sage 300 Construction and Real Estate 9.4 (or prior) to version 9.5 (or higher), opening an Excel workbook containig Office Connector features results in a prompt for user name and password.  After entering a valid user name and password, you receive the following message:

The user name or password you entered is incorrect.  Please enter a valid user name and password
<OK>

Resolution
The data folder path associated with the workbook must be changed to identify the UNC path that now used by Timberline.  To do so, follow these steps:

1.  Open the workbook
2.  When prompted to enter your user name and password, click Cancel
3.  Click Open Timberline Data Folder on the Office Connector toolbar.
4.  Select the appropriate company data folder and click OK
5.  Enter your user name and password and click OK