Ian
Very kind - but I've managed to resolve the issues for now. It was the tempdb database filling up (pegged at 2*MB*! Not a typo!) I extended logsegment using sp_extendsegment onto a newly-created database device (which is a logical mapping of a .dat file to a database object), made a couple of other configuration changes and the problems are solved.
I've still got a copy of Que's Computer Glossary (board-bound) on my shelf, explaining such modern concepts as 'parallel ports' and 'World Wide Web'!
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Note to developers:Want to get the best help? Click here https://www.sqlservercentral.com/articles/forum-etiquette-how-to-post-datacode-on-a-forum-to-get-the-best-help (Jeff Moden)
My blog: http://uksqldba.blogspot.com
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