I was able to get the SQL Server instances on my computer this way:
You then get a nice HTML web page. You want to look for Database Services. You should see an instance name. Mine is called "SQLEXPRESS." So the combination of server name and instance would be MYCOMPUTER\SQLEXPRESS given that my computer name is MYCOMPUTER.
BTW, the default instance name is MSSQLSERVER.
Alternatively, you can get it from your registry. Just run regedit and look for this key: Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\Instance Names\SQL
After spending lot of time, I found the solution!
As I mentioned, I had to log into Win10 with User10 and at the same time log into Win7, using User7.
Looks like connection was successful when I log into both PC with the same username.
So, I ended up to run SSMS as different user (in each PC) to be able connect to the other one.
On Win10 PC, I created a shortcut to run SSMA as User7, and this way I was able to connect to WIn7 PC and also created the shortcut in Win7 PC to run the SSMS as User10 to be able to connect to Win10 PC.
This link (FIX Connection) also might be helpful, it did not help me though.
This is the link to create shortcut to run as different user
i'm not sure to have a good view of what you are doing...
But i can say that SASS service is not included with sql server express. You can only have the reletional database service .\SQLEXPRESS, not the analytics database that is SSAS.
https://learn.microsoft.com/en-us/analysis-services/analysis-services-features-supported-by-the-editions-of-sql-server-2016?view=asallproducts-allversions
Instead of Express edition, download devenloper edition. It's free for not production env and full of features like enterprise edition. So you can test everything. Don't use it in production.
During sql dev setup be sure to select SASS instance too:
