As mentionned in the previous post I spent some time editing the home.php file of the default theme of the WPMU installation but in the end decided to change the theme to Tarski for the main blog. This looks very nice. It hasn’t got the display of recently updated blogs but this is not an issue for the moment and I assume I would be able to achieve this with a plugin of some sort.

One of the Tarski options is to upload a custom header image. However, despite increasing file permissions to the apparently problematic directories, as identified in the error message below, I could not upload an image.

Unable to create directory …………../wp-content/blogs.dir/1/files. Is its parent directory writable by the server?

I noticed that under Tarski options there is displayed a number of alternative headers pre-installed. I located the folder these were stored in and uploaded my custom header there using ftp. It was not listed and available for selection until I had also created and uploaded a 150×150 thumbnail for it with the required file name. Once this was done I could select the required custom header image and all was well. Perhaps uploading an individual custom header files using the custom header option doesn’t work with the theme in a WPMU installation. I have tried to do this with a test blog and it doesn’t work there either. If I can’t get this to work then users will only be able to use header iamges I have uploaded to the theme header folder.