Thanks for the various comments; my conclusions: - The problem was caused by erroneous use of 'const'. Now resolved. - The same error msg does occur in gcc 3.3.5, but in my case had been masked by a (long) cast e.g. the line str >> (long) pal.used; does not get flagged as an error. - It would have been easier to solve if the error message had flagged the incorrect use of 'const'. I must gen up on 'const' a bit... AM ___________________________________________________________ Tiscali Broadband from 14.99 with free setup! http://www.tiscali.co.uk/products/broadband/