Profiles remembering wrong proxy address?

[Ditto]

We recently moved from our previous ISP to RM Broadband. Part of the switch meant turning off Smoothwall and changing the proxy address to the usual proxy.rmplc.co.uk. I'm told Win7 and Win10 policy updates have been changed to point to the appropriate IP address. The issue we are seeing is quite a large number of pupils, when logging on to a Win10 PC, are not getting access to the internet with a proxy error being reported which I believe is to our old proxy address. It appears this is restricted to Win10 PCs - we still have a lot of Win7 PCs out there. Any suggestions on how to find the underlying issue and resolve very much welcome. As a side note, getting the pupils to logoff, deleting their profile and getting them to login again resolves the problem. Slightly frustratingly, deleting profiles has become this schools equivalent to 'Have you tried turning it off, then on again' to so many numerous issues. Even more annoyingly, it often resolves the immediate issue, but does nothing to find the root cause and avoiding the endless repeats with other users. Edited May 15, 2019 by Ditto

[Hybrid]

Have you ran GP Results for some of the affected users to see if there's a proxy setting hidden inside of one of the GPOs?

 

I've seen this issue when 'Automatically detect proxy settings' isn't ticked too. I've also seen an issue whereby you can load up Edge or IE, then load Chrome and it magically just works.

[Chockster]

We had a similar issue and it turned out to be a DFSR replication problem on one of our DCs. The GP that set the proxy hadn't been replicated to one of our three DCs (Don't ask -long story) so users had a one in three chance of getting the wrong proxy. The GP result reported things correctly, but the actual files on disk were incorrect. Something along the lines of the problem tackled here.

[Ditto]

Thanks for the suggestions. NM had a look today. Automatically detect isn't on, so might be one to try. We took a snapshot of a profile today that hit the issue. We have tracked down the old IP address in NTUSER.dat - just gotta figure out how/why it's getting there. We've also confirmed it is only hitting W10, and we believe only after the pupil/teacher has previously been on a W7 - but not exclusively the reason we don't think