MS Analysis Server 2005 DB Refresh issue

[swati]

One of my company's clients have a 2GB MS Analysis Services(AS 2005)
Database with 3 cubes and 23 dimensions.
Every day the entire DB is processed to update the DB with new data.
The processing is done via a utility which executes xmla script to
process the DB using Process Full in a single transaction and a single
batch.
The dimensions are processed using process Update. The processing is
parallel.

Since few days, I/O error is being encountered while processing the DB
through the utility.
The error is seen while building indexes for one of the cubes and for
some of the dimensions’ attributes.

Sample Error log
2010-09-03 11:14:35,496 [14960] INFO Informance.Logger.CubeProcessor
[(null)] - Errors in the OLAP storage engine: An error occurred while
processing the indexes for the main partition of the main measure
group of the main cube from the RateModule2 database.
Server: The operation has been cancelled.
Errors in the OLAP storage engine: An error occurred while processing
the indexes for the main partition of the main measure group of the
main cube from the RateModule2 database.
File system error: An I/O error was encountered during a sequential
read or write operation: There is not enough space on the disk. .
The following system error occurred from a call to GetOverlappedResult
for Physical file: '\\?\F:\Program Files\Microsoft SQL Server\MSSQL.
2\OLAP\Data\RateModule2.1.db\main.0.cub\main 1.0.det\main.0.prt
\497.ReasonGroup.Reason Category Name attribute.agg.flex.map.hdr',
Logical file: '' : There is not enough space on the disk. .

The error seen is - "There is not enough space on disk".
While there is abundant (111 GB) space on the AS Server where the OLAP
Data files exist.

The error is mainly seen for dimensions that store string values and
doesn’t not have much data.

We tried several solutions to make the processing work but none of
them worked.

a) changed ProcessingGroup setting for all dimensions from ByTable to
ByAttribute.

b) processed dimensions using Process Full to overwrite the .asstore
file if beyong 4GB.

c) Added dimensions processing code to the utility to process the
dimensions before the DB.

d) changed AttributeHierachyOptimizedState setting to NotOptimized
from FullyOptimized for attributes throwing error to decrease the
memory required for building indexes.

None of these solutions have worked successfully.

The DB is successfully processed using the utility only if all the
dimensions are manually processed one by one on the AS Server before
the utility execution. This is the only option that works.

Here is the configuration information for AS Server
Operating System - MS Windows Server 2003, x64 Enterprise Edition, SP2
RAM - 3 GB
Hard Disk Space - Total 184GB , Free 111 GB
AS Server Version - 9.00.4200.00
AS Database - 2GB

Please let me know of any solution for this problem.