Error message when you create timesheet periods in Project Server 2007: "DataSource property must be set to DataSet, DataTable or XmlGridBinding"

When you try to create timesheet periods in Microsoft Office Project Server 2007, you may receive the following error message:

This issue occurs if the name of the computer on which Project Server 2007 is installed contains an underscore character (_).

To resolve this issue, rename the computer so that the computer name does not contain the underscore character.

For a new server, follow these steps:

1. Click Start, click Run, type sysdm.cpl, and then click OK.
2. In the System Properties dialog box, click the Computer Name tab, and then click Change.
3. In the Computer Name Changes dialog box, in the Computer name box, type a new computer name that does not contain an underscore character and then click OK.

For an existing server on which several services depend, follow these steps:

1. Create an alias (CNAME) that does not contain an underscore character in the Domain Name System (DNS) server. To do this, follow these steps:
   1. Click Start, point to Administrative Tools, and then click DNS.
   2. Expand ServerName, and then expand Forward Lookup Zones.
   3. Right-click the default zone, and then click New Alias (CNAME).
   4. In the Alias name (uses parent domain if left blank) box, type an alias that does not contain an underscore character.
   5. In the Fully Qualified domain name (FQDN) for the host box, type a suitable name.
   6. Click OK.
2. In SharePoint Central Administration, change the alternate access mapping to the new alias. To do this, follow these steps:
   1. Click Start, point to Administrative Tools, and then click SharePoint 3.0 Central Administration.
   2. On the Central Administration page, click Operations.
   3. Under Global Configuration, click Alternate Access Mapping.
   4. On the Alternate Access Mappings page, click the internal URL where the Project Web Access (PWA) site is provisioned for the default zone.
   5. In the URL protocol, host and port box, change the URL to the name that you entered in step 1.e.