I'm not finding the thread where people are talking about this. Is there one?  Is everyone with 1803 seeing it, or are there variables?

Anyway, to save people from finding the KB:

1. Click Windows Start button, then Control Panel, and select Network & Sharing Center.
2. Click Change adapter settings (top left hand corner).
3. Right-click network connection, and then select Properties.
4. Under Networking tab uncheck Internet Protocol Version 6 (TCP/IPv6) box.
5. Click OK.
6. Reboot your computer.

We were getting a lot of calls on it, and we'll get more because it's caused by a Microsoft update.

This is interesting. The U.S. edition (a completely different lineage than Sage 50 CA, as I understand it) also has problems with it, but one of the potential workarounds is the same. Sage won't be able to do anything about it in their case though.

https://sagecity.na.sage.com/support_communities/sage50_accounting_us/f/sage-50-accounting---u-s-edition/108237/advisory-windows-10-spring-creators-update-v1803

I notice that an update for 1803 this week fixed an issue with QuickBooks. I assume, but don't know, that it wouldn't help with either Sage problem.

support.microsoft.com/.../4284835

Thanks!

Just in case it helps, I tested this out on a Windows Server 2016 network, with the client PC being W10 1803 (17134.112, the latest revision), and Sage 2018.2 (not .3, which apparently just came out). Can't reproduce the problem. IPv6 is enabled.

Should .3 be safe to install, or is it possible that it's key to the problem?  There are so many variables in this that it's hard to say from here.