importing error

We have a wordpress multisite, and because of recent (still unresolved) cpu usage spikes we exported the archive section of the site to see if this made any difference.

As it hasn’t we want to import it again.

However we have been unable to import it as we keep getting error messages.

This part of the multisite was originally imported from a stand alonge blog so we know there was not problem with this.

Have recent updates to worpress changed how the import function works as it now indicates a plugin which earlier versions didn’t need.

We have installed this and are concerned it doesn’t recognise the export file.

Or worse still the export did not work which means not only have we lost the archive files, but the back up we make of the multisite will turn out to be worthless.

Please note the size of the file is 20,056Kb and the uploader max is set to 64MB.

And we were able to import it originally 2 years ago.

Can anyone help us resolve this.

Thanks