ACER Aspire 5552(62 bit) with the WIN7 OS. It was printing normally till yesterday and thereafter it continued to display the usual lights and to make the usual printing noises but no marks appeared on the paper-though ink supply adequate and no changes/additions have been made to the software or hardware in the meantime. A scan with the latest Print and Scan Doctor showed all functions to be normal, except that it would not print a test page nor an internal one. When it failed to do the latter it said `there may be a serious issue' but offered no further information or advice. I would much appreciate advice on fixing this problem.Thanks.