Exchange 2019 internet calendar sharing doesn't work after CU11

Question

Hi!

After installing CU11 on Exchange server 2019 users report that internet calendar sharing doesn't work.

I can successfully create "Share calendar" message, but if I click the link it reports 404 error.

Some external services that were previously using this link doesn't have access either.

Please help.

Best regards, Alex

Answer 1

Hi!

I opened a support ticket and after 12 days of waiting I've got an answer from support engineer which fixed the problem.
The issue is described here https://social.technet.microsoft.com/Forums/ie/en-US/2229748b-b083-4bd1-9410-888ecbbdc987/url-is-not-valid-error-when-attempting-to-publish-internet-calendar-exchange-2010-sp1?forum=exchange2010

I checked my internal and external URL for OWA virtual directory and both was just owa.domain.ru, changing both to owa.domain.ru/owa fixed the problem.
Not sure this is good solution because previously it worked fine with this settings
but it works so I'll just check that no other issues will appear.

Answer 2

Your question:

<#Hmm, I've got no Rewrite rules in my owa directory.
Is it ok if I have all roles on the same server?

>

EvandroBoaSemedo-7272 EvandroBoaSemedo-7272 56522859 · (just now)

This is not a problem, i do this too in my all servers with the same url rewrite rules.

If you restore your web.config to default, the owa calendar back to works or if you edit and saving.

There is a bug in url rewrite, somehow it's not being imported correctly causing some code failure. If you create any rule that is, invalid or valid and apply it, it will work again. If you delete the rule, however invalid it may be, it also works again, as the web.config structure ends up being corrected in some way.

C:\Program Files\Microsoft\Exchange Server\V15\FrontEnd\HttpProxy\owa\web.config

vDIR Export Rules
cd "C:\Windows\System32\inetsrv"
appcmd list config "Default Web Site/owa" -section:system.webServer/rewrite/rules -xml > P:\owarewriterules.xml

vDIR Import Rules
cd "C:\Windows\System32\inetsrv"
appcmd set config "Default Web Site/owa" -in < P:\owarewriterules.xml

I solved my problem editing my web-config and save it, because the failure was in the structure of the web.config imported from the backup xml by the cmd prompt itself.

But, looks like a bug.

Answer 3

I have the similar problem.

https://learn.microsoft.com/en-us/answers/questions/600987/anonymous-calendar-sharing-url-in-exchange-is-not.html?childToView=606759#answer-606759

https://social.technet.microsoft.com/Forums/pt-BR/b4f42207-14ba-4788-8528-6819fc58bd74/anonymous-calendar-sharing-url-in-exchange-is-not-working-between-exchange-20162019-coexistence?forum=reportabug

Answer 4

I would open a ticket with Microsoft Support.

Answer 5

If I try to set Public calendar permission, I receive error 500 and this error in HttpProxy Log
Does this mean it's backend error?

2021-11-18T11:03:32.148Z,2b24718a-da90-4881-8340-4070d69d6edd,15,2,986,14,551DBC4AE16747BEA4CAF5A1BC07C9EC_163723341204762,Owa,mail.domain.ru,/owa/service.svc,SetCalendarPublishing,FBA,true,DOMAIN\tester3,,Sid~S-1-5-21-3418564623-3015839265-525170019-2703,Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML like Gecko) Chrome/94.0.4606.81 Safari/537.36 OPR/80.0.4170.63,172.25.0.65,MXM,500,500,,POST,Proxy,mail.domain.local,15.02.0986.000,IntraForest,WindowsIdentity,Database~1ddd6ccf-be67-4cff-8809-6fe9619d437f~~2021-12-18T11:03:28,,,0,301,,,2,0,,0,,0,,0,0,,0,42,0,,,,38,0,0,1,0,0,40,0,39,1,1,3,42,,?action=SetCalendarPublishing&EP=1&ID=-43&AC=1,,ClientId=551DBC4AE16747BEA4CAF5A1BC07C9EC;BeginRequest=2021-11-18T11:03:32.106Z;CorrelationID=551DBC4AE16747BEA4CAF5A1BC07C9EC_163723341204762;ProxyState-Run=None;FEAuth=BEVersion-1942127578;BeginGetResponse=2021-11-18T11:03:32.109Z;OnResponseReady=2021-11-18T11:03:32.147Z;EndGetResponse=2021-11-18T11:03:32.147Z;ProxyState-Complete=ProxyResponseData;SharedCacheGuard=0;EndRequest=2021-11-18T11:03:32.148Z;,WebExceptionStatus=ProtocolError;ResponseStatusCode=500;,,|RoutingDB:1ddd6ccf-be67-4cff-8809-6fe9619d437f,,,CafeV1