ME 045 — ME 045 — G/L Account Cannot Be Used in Purchase Requisition or Order

ME 045 states that the selected G/L account cannot be used and should be corrected. SAP support links the message to incompatibilities between purchasing account-assignment data and the G/L account's field status. The purchasing document may use an account-assignment category that suppresses a field while the G/L account configuration requires that same field. SAP detects that the resulting accounting line could not be valid and blocks or warns before later goods receipt or invoice posting.

A G/L account may require cost center, WBS element, order or another assignment that the chosen purchasing account-assignment category does not provide. Field selection in purchasing and field status in FI can conflict. Users may manually select a G/L account that belongs to a different business purpose. Automatic account determination or account-defaulting logic can propose an incompatible account. Configuration copied from another company code can also create inconsistent field-status behavior. SAP support notes that if the mismatch is not caught in purchasing, a later goods receipt may fail with F5 808.

Identify the PR or PO item, account-assignment category and G/L account. Check which account-assignment objects the purchasing category permits or hides. In FS00, inspect the G/L account field status group and identify fields set as required. Compare the two controls field by field. Review whether the G/L was entered manually, defaulted from account assignment or derived through configuration. If ME 045 behaves differently than expected despite message settings, inspect the standard purchasing check behavior for the release rather than assuming OMRM-style message control applies. Compare a working G/L account used with the same account-assignment category.

Use a G/L account whose required fields are compatible with the purchasing account-assignment category, or correct the account-assignment category when the business process genuinely needs the additional object. If the G/L field status is too restrictive for all legitimate uses of the account, FI can redesign it after impact analysis. If automatic derivation proposes the wrong account, correct that determination source instead of asking users to override every document. Retest purchase requisition/order creation and the downstream GR/invoice posting because the goal is not only to remove ME 045 but to ensure the eventual accounting document is valid.

Making the FI field optional just to let a PO through can weaken accounting data quality across many unrelated processes. Conversely, exposing every purchasing account-assignment field can create confusing or invalid combinations for users. Another workaround is to select a random G/L that happens to pass the check. The fix should align purchasing account assignment with the economic nature of the G/L account, not merely bypass validation.

MM Purchasing owns the account-assignment category and purchasing field selection. FI owns the G/L account and field status. CO or PS may own the underlying cost center, order or WBS requirement. ABAP/integration teams are relevant only if custom logic proposes the wrong G/L or strips required account-assignment data. The issue is best resolved jointly by MM and FI because changing either side alone can create a valid purchasing screen but invalid accounting later.

Do not troubleshoot ME 045 using only the message severity. First prove the field incompatibility. Check the exact account-assignment category, not only the document type. G/L field status can differ between accounts that look similar. If users report that ME 045 is missing but GR later fails with F5 808, that is a clue that the incompatibility still exists. After configuration changes, test PR, PO, GR and invoice steps end to end.