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I have a requirement to build a SSIS package that sends HTML formatted emails and then saves the emails as tiff files. I have created a script task that processes the necessary records and then coverts the HTML code to the tiff. I have split the process into separate packages, the email send works fine the converting HTML to tiff is causing the issue.

When running the package manually it will process all files without any issues. my test currently is about 315 files this needs to be able to process at least 1,000 when finished with the ability to send up to 10,000 at one time. The problem is when I set the package to execute using SQL Server Agent it stops at 207 files. The package is deployed to SQL Server 2019 in the SSIS Catalog

What I have tried so far

I started with the script being placed in a SSIS package and deployed to the server and calling the package from a step (works 99.999999% of the time with all packages) tried both 32 and 64 bit runtime. Never any error messages just Unexpected Termination when looking at the execution reports. When clicking in the catalog and executing package it will process all the files. The SQL Server Agent is using a proxy and I also created another proxy account with my admin credentials to test for any issues with the account.

Created another package to call the package and used the Execute Package Task to call the first package, same result 207 files. Changed the execute Process task to an Execute SQL Task and tried the script that is created to manually start a package in the catalog 207 files. Tried executing the script from the command line both through the other SSIS package and the SQL Server Agent directly same results 207 files. If I try any of those methods directly outside SQL Server Agent the process runs no issues.

I converted the script task to a console application and it works processing all the files. When calling the executable file from any method from the SQL Server Agent it once again stops at the 207 files.

I have consulted with the companies DBA and Systems teams and they have not found anything that could be causing this error. There seems to be some type of limit that no matter the method of execution SQL Server Agent will not allow. I have mentioned looking at third-party applications but have been told no.

I have included the code below that I have been able to piece together. I am a SQL developer so C# is outside my knowledge base. Is there a way to optimize the code so it only uses one thread or does a cleanup between each letter. There may be a need for this to create over ten thousand letters at certain times.

Update

I have replaced the code with the new updated code. The email and image creation are all included as this is what the final product must do. When sending the emails there is a primary and secondary email address and depending on what email address is used it will change what the body of the email contains. When looking at the code there is a section of try catch that sends to primary when indicated to and if that fails it send to secondary instead. I am guessing there is a much cleaner way of doing that section but this is my first program as I work in SQL for everything else.

Thank You for all the suggestions and help.

Updated Code