That seems to have fixed it - Any chance of a copy of what ever is needed to put that on one of my web sites? Then all I would need is an automated method to upload the file regularly

[EDIT] It is showing 9.3mm of rain in the last hour on the site - my station was showing nil, but has suddenly shot up to a silly value. There has been no rain, honest. I think the problem is that the file becomes corrupted, when two things access it at the same time - my station writing to it whilst at the same time sending the file to your web site.