Lost 15GB hdd space overnight

Have you checked and/or cleared System Restore Points? The more space you clear the more you make available for this.

I've cleared out all system restore points. I'm loosing space by the hour/minute, not just overnight  

I've lost 1GB since posting this question.  

It seems like search indexer and sqldumper are doing a lot of things???

So I ended the Search Indexer process and it restarted itself!!  

OK, I've found an SQL Server Log folder that has 49,000 items in it. Every third one is at least 1.2 MB in size. The names are something like SQLDump0001.txt .mdmp and .log Do I need all these? Can I delete all of them? How can I stop the SQL Server from dumping in this folder? Thanks for your help so far!

Not a great deal of help, but have a look at this thread, which explains these files. It may give you some ideas to work on. Presumably you know that you are running SQL server - what do you use it for? It sounds as though, for some reason, you are getting access errors, which are creating all these files.

Don't forget that whatever the size of the file it occupies at least one cluster on your disk so even if the files are tiny they can soon add up to quite a space. The good news is you can delete the files.

Don't worry about the Search Indexer - it may be that this is trying to index the other files as they are being created. But, normally, indexing your disk is a good thing.

Hope this points to a line of investigation. Good luck!

Well, I uninstalled all the SQL server programs. I think they were related to ActiveSync, which I no longer use. I deleted all the log, txt, etc. files and recovered 26GB of space. Problem taken care of. But still don't know what triggered it. I don't really care though. Thanks for prompting me to look around other places on my computer it helped me fix the problem.

Best answer selected by JeffVoegtlin.