I called Sage about this issue on Tuesday. I needed to add an Il UC rate change beginning 1/1/2020 and received the same message.
I talked to Ryan at Sage about the IL unemployment insurance wage limit issue we discussed (support case# 8007920065). He said the limit is kept on a cloud server and is not maintained in Sage 100. He also mentioned that the message that was displaying in payroll setup, company tax group maintenance, "The Alternate wage cap is required" is only applicable to Rhode Island and another state, not Illinois.
I created a new record in PR_CompanyTaxGroupRates.M4T by modifying the 1/1/2019 record and answering "No" to delete the existing record.
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Doug Higgs
Midwest Commerce Solutions, Inc
(312) 315-0960
"Would you tell me, please, which way I ought to go from here?"
"That depends a good deal on where you want to get to."
Oscar Wilde - Alice in Wonderland
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