Error installing ODBC driver

I apologize if this is posted twice; I tried to post on Friday but it looks like it didn't go through.

I have an MS Access program that has drawn data from a postgresql database for years.
Now the program crashes before the postgresql login screen appears.
I decided to reinstall the driver, so removed it through control panel first.

When I attempt to reinstall the postgresql driver, i get:
"Error 1918: error installing odbc driver.  component not found in the registry.  Verify that the file PostgreSQL
existsand that you can access it." 

I am using ver. 7.03.02.00 postgresql driver.
Yes I know it is old, but up to now has worked flawlessly.

Any ideas why the driver install fails?  I searched the archives but found nothing relevant.
Search on 1918 yields nothing related to this, as does (not) other terms in the message.

Thanks in advance for any help.

Fred