Just a few points about running classic reports from RTC, based on common support scenarios:
RUNMODAL (Not possible)
RTC runs classic reports (reports with no RDL Layout) by starting the report engine from a classic client. However, RTC is not able to run classic reports MODALLY. RUNMODAL as opposed to just RUN means that execution of the next line of C/AL code waits until the report has completed. Of course RTC reports which DO have a layout can run MODALLY without any problems.
So Report.RUNMODAL on a classic report from RTC does exactly the same as Report.RUN, i.e. RTC will launch the classic report engine but not wait for the report to finish before executing the next line of code. In most cases this doesn't matter. But the challenge is when the next line of code dependeds on the report having completed, for example to email the report, convert it to pdf, write back a result of the report to the database, or something else.
Running batches of classic reports (Improvement)
The good news is that there has been a few small other improvements relating to running classic reports from RTC. When the classic client closes, it updates a few files like the .zup file, and in the case of breakpoints having been used, also NaviBP.xml as described here:
In case we launched a batch of classic reports, one instance of the classic report engine would start up for each report. And each instance could overwrite each other's files, leading to error messages like this:
You cannot use the file C:\Users\[USER]\AppData\Roaming\fin.zup because it is already in use.
Microsoft Visual C++ Runtime Library
This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.
But with KB 2398170 (build 31587) the behaviour is changed, so that now when the classic client closes the report engine, it willl 1) only try to update the .zup file, and 2) not try to update naviBP.xml at all, avoiding the error messages mentioned above.
Licenses (No, it doesn't consume a license)
When you run a classic report from RTC, this does NOT consume a user license. If you watch the Session table while a classic report is running, you will see that a new session has connected, but with "Application Name" = '111'. In this way the system knows not to count it as a normal NAV client, so it will not count as a concurrent session.
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