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Integer tolerance must be a small positive number.

The value for Tolerance must be greater than or equal to 0 and less than 100. A zero value ensures that the Solver will find the true integer optimal solution -- possibly at the expense of much greater solution time. For a full discussion of this option, click on Precision and Tolerance [TBD].

Load Model: Invalid Set Cell formula.
Load Model: Invalid Adjustable Cells reference.
Load Model: Invalid constraint formula.

One of these messages may appear when you select Load Model... and click OK in the resulting dialog, after you OK the confirmation message (shown below). The particular message which appears indicates the source of the error.

The first cell in the Load Model area contains the Set Cell formula, in the form =MAX(cell), =MIN(cell) or =cell=value. The second cell contains a reference to the adjustable cells in the form =COUNT(adjustables). Subsequent cells contain constraints, in the form of logical formulas such as =A1>=0; these may be array formulas if the corresponding constraint is defined over a range of cells.

If you receive one of these error messages, you may have accidentally modified the Load Model area, either interactively or through your own VBA code.

Max Time or Iterations must be a positive number.

The value for Max Time (in seconds) and Iterations must be an integer between 1 (which doesn't allow much time) and 32767. If the maximum time or iterations is reached, you can still allow the solution process to proceed by clicking on Continue in the Show Trial Solutions dialog. For more information on these options, consult Max Time and Iterations [TBD].

Model cannot be saved in this area.

This message appears when you try to save the current Solver model in an area of the worksheet where cell values cannot be stored, perhaps because the cells are protected or because they are part of an array. Choose another area and try again.

Precision must be a small positive number.

The value for Precision must be strictly greater than 0 and less than 1. In almost all cases, it should be kept in the range of 1E-4 (0.0001) to 1E-8, and for most purposes the default value of 1E-6 is recommended. For a full discussion of this option, click on Precision and Tolerance [TBD].

Reference not large enough to hold model; N cells required.

This message appears when you select Save Model... and specify a range of cells which is not large enough to hold all of the information about the Solver model. The message indicates how many cells are needed; more cells may be specified, but only the first N cells will be used. Adjust the size of the cell reference you have specified and click OK again.

Reset previous Solver cell selections?

This is a confirmation message which appears when you select Load Model and click OK in the resulting dialog. If you OK this confirmation message, the Solver will erase any existing adjustable cell, target cell and constraint information, then attempt to load a Solver model from the area you specified. If errors are detected in the process of loading the new model, the old model information will be lost. Click OK if you are sure it is safe to continue.

Back to Standard Excel Solver:  Help with Specific Solver Messages

Back to Standard Excel Solver Support Information