Sharepoint Folder Credential Error When Refreshing Report Server

Hello,

I have a report that sources data from an excel workbook in a corporate Sharepoint folder. Refreshing from Dekstop works perfectly, but once I publish to the report server, the data will not refresh. I receive this error:

SessionID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxx

[0] -1055784932: The credentials provided for the SharePoint source are invalid. (Source at https://collaborate.xxxx.com/c/xxxxx.). The exception was raised by the IDbCommand interface.

[1] -1055784932: The command has been canceled.. The exception was raised by the IDbCommand interface.

[2] -1055784932: The command has been canceled.. The exception was raised by the IDbCommand interface.

[3] -1055784932: The command has been canceled.. The exception was raised by the IDbCommand interface.

[4] -1055784932: The command has been canceled.. The exception was raised by the IDbCommand interface.

[5] -1055784932: The command has been canceled.. The exception was raised by the IDbCommand interface.

[6] -1055784932: The command has been canceled.. The exception was raised by the IDbCommand interface.

[7] -1055784932: The command has been canceled.. The exception was raised by the IDbCommand interface.

[8] -1055784932: The command has been canceled.. The exception was raised by the IDbCommand interface.

[9] -1055784932: The command has been canceled.. The exception was raised by the IDbCommand interface.

I have entered my Windows credentials in the Data Source pane, and the Test comes back working. But every time I try to run a refresh, schedule or manual, the same error.

Do I need to add something prior to my Windows login name, like the name of the company. When I log onto my computer, I only use my username.

Is there something I am missing.